MINOR: http: Add support for http 413 status

Add 413 http "payload too large" status code. This will allow 413 to be
used in deny_status and errorfile.
diff --git a/doc/configuration.txt b/doc/configuration.txt
index 186d9a8..2d8e465 100644
--- a/doc/configuration.txt
+++ b/doc/configuration.txt
@@ -3927,7 +3927,7 @@
   Arguments :
     <code>    is the HTTP status code. Currently, HAProxy is capable of
               generating codes 200, 400, 401, 403, 404, 405, 407, 408, 410,
-              425, 429, 500, 502, 503, and 504.
+              413, 425, 429, 500, 502, 503, and 504.
 
     <file>    designates a file containing the full HTTP response. It is
               recommended to follow the common practice of appending ".http" to
@@ -3976,7 +3976,7 @@
 
     <code>  is a HTTP status code. Several status code may be listed.
             Currently, HAProxy is capable of generating codes 200, 400, 401,
-            403, 404, 405, 407, 408, 410, 425, 429, 500, 502, 503, and 504.
+            403, 404, 405, 407, 408, 410, 413, 425, 429, 500, 502, 503, and 504.
 
   Errors defined in the http-errors section with the name <name> are imported
   in the current proxy. If no status code is specified, all error files of the
@@ -4002,7 +4002,7 @@
   Arguments :
     <code>    is the HTTP status code. Currently, HAProxy is capable of
               generating codes 200, 400, 401, 403, 404, 405, 407, 408, 410,
-              425, 429, 500, 502, 503, and 504.
+              413, 425, 429, 500, 502, 503, and 504.
 
     <url>     it is the exact contents of the "Location" header. It may contain
               either a relative URI to an error page hosted on the same site,
@@ -4034,7 +4034,7 @@
   Arguments :
     <code>    is the HTTP status code. Currently, HAProxy is capable of
               generating codes 200, 400, 401, 403, 404, 405, 407, 408, 410,
-              425, 429, 500, 502, 503, and 504.
+              413, 425, 429, 500, 502, 503, and 504.
 
     <url>     it is the exact contents of the "Location" header. It may contain
               either a relative URI to an error page hosted on the same site,
@@ -5009,8 +5009,8 @@
   Arguments :
     status <code>        is the HTTP status code. It must be specified.
                          Currently, HAProxy is capable of generating codes
-                         200, 400, 401, 403, 404, 405, 407, 408, 410, 425, 429,
-                         500, 502, 503, and 504.
+                         200, 400, 401, 403, 404, 405, 407, 408, 410, 413, 425,
+                         429, 500, 502, 503, and 504.
 
     content-type <type>  is the response content type, for instance
                          "text/plain". This parameter is ignored and should be
@@ -5453,22 +5453,22 @@
 
   * If "default-errorfiles" argument is set, the proxy's errorfiles are
     considered.  If the "status" argument is defined, it must be one of the
-    status code handled by hparoxy (200, 400, 403, 404, 405, 408, 410, 425,
-    429, 500, 502, 503, and 504). The "content-type" argument, if any, is
-    ignored.
+    status code handled by hparoxy (200, 400, 403, 404, 405, 408, 410, 413,
+    425, 429, 500, 502, 503, and 504). The "content-type" argument, if any,
+    is ignored.
 
   * If a specific errorfile is defined, with an "errorfile" argument, the
     corresponding file, containing a full HTTP response, is returned. Only the
     "status" argument is considered. It must be one of the status code handled
-    by hparoxy (200, 400, 403, 404, 405, 408, 410, 425, 429, 500, 502, 503, and
-    504). The "content-type" argument, if any, is ignored.
+    by hparoxy (200, 400, 403, 404, 405, 408, 410, 413, 425, 429, 500, 502, 503,
+    and 504). The "content-type" argument, if any, is ignored.
 
   * If an http-errors section is defined, with an "errorfiles" argument, the
     corresponding file in the specified http-errors section, containing a full
     HTTP response, is returned. Only the "status" argument is considered. It
     must be one of the status code handled by hparoxy (200, 400, 403, 404, 405,
-    408, 410, 425, 429, 500, 502, 503, and 504). The "content-type" argument,
-    if any, is ignored.
+    408, 410, 413, 425, 429, 500, 502, 503, and 504). The "content-type"
+    argument, if any, is ignored.
 
   * If a "file" or a "lf-file" argument is specified, the file's content is
     used as the response payload. If the file is not empty, its content-type
@@ -6100,22 +6100,22 @@
 
   * If "default-errorfiles" argument is set, the proxy's errorfiles are
     considered.  If the "status" argument is defined, it must be one of the
-    status code handled by hparoxy (200, 400, 403, 404, 405, 408, 410, 425,
-    429, 500, 502, 503, and 504). The "content-type" argument, if any, is
-    ignored.
+    status code handled by hparoxy (200, 400, 403, 404, 405, 408, 410, 413,
+    425, 429, 500, 502, 503, and 504). The "content-type" argument, if any,
+    is ignored.
 
   * If a specific errorfile is defined, with an "errorfile" argument, the
     corresponding file, containing a full HTTP response, is returned. Only the
     "status" argument is considered. It must be one of the status code handled
-    by hparoxy (200, 400, 403, 404, 405, 408, 410, 425, 429, 500, 502, 503, and
-    504). The "content-type" argument, if any, is ignored.
+    by hparoxy (200, 400, 403, 404, 405, 408, 410, 413, 425, 429, 500, 502, 503,
+    and 504). The "content-type" argument, if any, is ignored.
 
   * If an http-errors section is defined, with an "errorfiles" argument, the
     corresponding file in the specified http-errors section, containing a full
     HTTP response, is returned. Only the "status" argument is considered. It
     must be one of the status code handled by hparoxy (200, 400, 403, 404, 405,
-    408, 410, 425, 429, 500, 502, 503, and 504). The "content-type" argument,
-    if any, is ignored.
+    408, 410, 413, 425, 429, 500, 502, 503, and 504). The "content-type"
+    argument, if any, is ignored.
 
   * If a "file" or a "lf-file" argument is specified, the file's content is
     used as the response payload. If the file is not empty, its content-type
diff --git a/include/haproxy/http-t.h b/include/haproxy/http-t.h
index c8bf9a3..500fc46 100644
--- a/include/haproxy/http-t.h
+++ b/include/haproxy/http-t.h
@@ -90,6 +90,7 @@
 	HTTP_ERR_407,
 	HTTP_ERR_408,
 	HTTP_ERR_410,
+	HTTP_ERR_413,
 	HTTP_ERR_421,
 	HTTP_ERR_425,
 	HTTP_ERR_429,
diff --git a/src/http.c b/src/http.c
index b798c5d..7278cad 100644
--- a/src/http.c
+++ b/src/http.c
@@ -165,6 +165,7 @@
 	[HTTP_ERR_407] = 407,
 	[HTTP_ERR_408] = 408,
 	[HTTP_ERR_410] = 410,
+	[HTTP_ERR_413] = 413,
 	[HTTP_ERR_421] = 421,
 	[HTTP_ERR_425] = 425,
 	[HTTP_ERR_429] = 429,
@@ -249,6 +250,14 @@
 	"\r\n"
 	"<html><body><h1>410 Gone</h1>\nThe resource is no longer available and will not be available again.\n</body></html>\n",
 
+	[HTTP_ERR_413] =
+	"HTTP/1.1 413 Payload Too Large\r\n"
+	"Content-length: 106\r\n"
+	"Cache-Control: no-cache\r\n"
+	"Content-Type: text/html\r\n"
+	"\r\n"
+	"<html><body><h1>413 Payload Too Large</h1>\nThe request entity exceeds the maximum allowed.\n</body></html>\n",
+
 	[HTTP_ERR_421] =
 	"HTTP/1.1 421 Misdirected Request\r\n"
 	"Content-length: 104\r\n"
@@ -351,6 +360,7 @@
 	case 407: return HTTP_ERR_407;
 	case 408: return HTTP_ERR_408;
 	case 410: return HTTP_ERR_410;
+	case 413: return HTTP_ERR_413;
 	case 421: return HTTP_ERR_421;
 	case 425: return HTTP_ERR_425;
 	case 429: return HTTP_ERR_429;