REORG: dgram: rename proto_udp to dgram

The set of files proto_udp.{c,h} were misleadingly named, as they do not
provide anything related to the UDP protocol but to datagram handling
instead, since currently all UDP processing is hard-coded where it's used
(dns, logs). They are to UDP what connection.{c,h} are to proto_tcp. This
was causing confusion about how to insert UDP socket management code,
so let's rename them right now to dgram.{c,h} which more accurately
matches what's inside since every function and type is already prefixed
with "dgram_".
diff --git a/src/check.c b/src/check.c
index 1a9938d..18f83fa 100644
--- a/src/check.c
+++ b/src/check.c
@@ -35,6 +35,7 @@
 #include <haproxy/cfgparse.h>
 #include <haproxy/check.h>
 #include <haproxy/chunk.h>
+#include <haproxy/dgram.h>
 #include <haproxy/dns.h>
 #include <haproxy/extcheck.h>
 #include <haproxy/fd.h>
@@ -49,7 +50,6 @@
 #include <haproxy/mailers.h>
 #include <haproxy/port_range.h>
 #include <haproxy/proto_tcp.h>
-#include <haproxy/proto_udp.h>
 #include <haproxy/protocol.h>
 #include <haproxy/proxy.h>
 #include <haproxy/queue.h>
diff --git a/src/proto_udp.c b/src/dgram.c
similarity index 89%
rename from src/proto_udp.c
rename to src/dgram.c
index f5202f8..54823d1 100644
--- a/src/proto_udp.c
+++ b/src/dgram.c
@@ -1,5 +1,5 @@
 /*
- * UDP protocol related functions
+ * Datagram processing functions
  *
  * Copyright 2014 Baptiste Assmann <bedis9@gmail.com>
  *
@@ -11,7 +11,7 @@
  */
 
 #include <haproxy/fd.h>
-#include <haproxy/proto_udp-t.h>
+#include <haproxy/dgram.h>
 
 /* datagram handler callback */
 void dgram_fd_handler(int fd)
diff --git a/src/dns.c b/src/dns.c
index 55b5a37..6f951ab 100644
--- a/src/dns.c
+++ b/src/dns.c
@@ -25,6 +25,7 @@
 #include <haproxy/channel.h>
 #include <haproxy/check.h>
 #include <haproxy/cli.h>
+#include <haproxy/dgram.h>
 #include <haproxy/dns.h>
 #include <haproxy/errors.h>
 #include <haproxy/fd.h>
@@ -32,7 +33,6 @@
 #include <haproxy/http_rules.h>
 #include <haproxy/log.h>
 #include <haproxy/net_helper.h>
-#include <haproxy/proto_udp.h>
 #include <haproxy/proxy.h>
 #include <haproxy/sample.h>
 #include <haproxy/server.h>
diff --git a/src/tools.c b/src/tools.c
index 0b7e77e..35936b5 100644
--- a/src/tools.c
+++ b/src/tools.c
@@ -41,12 +41,12 @@
 
 #include <haproxy/api.h>
 #include <haproxy/chunk.h>
+#include <haproxy/dgram.h>
 #include <haproxy/dns.h>
 #include <haproxy/global.h>
 #include <haproxy/hlua.h>
 #include <haproxy/listener.h>
 #include <haproxy/namespace.h>
-#include <haproxy/proto_udp.h>
 #include <haproxy/ssl_sock.h>
 #include <haproxy/stream_interface.h>
 #include <haproxy/task.h>