MEDIUM: regex: replace all standard regex function by own functions

This patch remove all references of standard regex in haproxy. The last
remaining references are only in the regex.[ch] files.

In the file src/checks.c, the original function uses a "pmatch" array.
In fact this array is unused. This patch remove it.
diff --git a/include/types/checks.h b/include/types/checks.h
index d5038eb..a50043b 100644
--- a/include/types/checks.h
+++ b/include/types/checks.h
@@ -177,7 +177,7 @@
 	/* sent string is string */
 	char *string;                           /* sent or expected string */
 	int string_len;                         /* string lenght */
-	regex_t *expect_regex;                  /* expected */
+	struct my_regex *expect_regex;          /* expected */
 	int inverse;                            /* 0 = regular match, 1 = inverse match */
 	unsigned short port;                    /* port to connect to */
 	unsigned short conn_opts;               /* options when setting up a new connection */
diff --git a/include/types/proto_http.h b/include/types/proto_http.h
index ff196a0..affc231 100644
--- a/include/types/proto_http.h
+++ b/include/types/proto_http.h
@@ -419,7 +419,7 @@
 			char *name;            /* header name */
 			int name_len;          /* header name's length */
 			struct list fmt;       /* log-format compatible expression */
-			regex_t* re;           /* used by replace-header and replace-value */
+			struct my_regex re;    /* used by replace-header and replace-value */
 		} hdr_add;                     /* args used by "add-header" and "set-header" */
 		struct redirect_rule *redir;   /* redirect rule or "http-request redirect" */
 		int nice;                      /* nice value for HTTP_REQ_ACT_SET_NICE */
@@ -445,7 +445,7 @@
 			char *name;            /* header name */
 			int name_len;          /* header name's length */
 			struct list fmt;       /* log-format compatible expression */
-			regex_t* re;           /* used by replace-header and replace-value */
+			struct my_regex re;    /* used by replace-header and replace-value */
 		} hdr_add;                     /* args used by "add-header" and "set-header" */
 		int nice;                      /* nice value for HTTP_RES_ACT_SET_NICE */
 		int loglevel;                  /* log-level value for HTTP_RES_ACT_SET_LOGL */
diff --git a/include/types/proxy.h b/include/types/proxy.h
index 33524f3..b33b634 100644
--- a/include/types/proxy.h
+++ b/include/types/proxy.h
@@ -343,7 +343,7 @@
 	char *check_req;			/* HTTP or SSL request to use for PR_O_HTTP_CHK|PR_O_SSL3_CHK */
 	int check_len;				/* Length of the HTTP or SSL3 request */
 	char *expect_str;			/* http-check expected content : string or text version of the regex */
-	regex_t *expect_regex;			/* http-check expected content */
+	struct my_regex *expect_regex;		/* http-check expected content */
 	struct chunk errmsg[HTTP_ERR_SIZE];	/* default or customized error messages for known errors */
 	int uuid;				/* universally unique proxy ID, used for SNMP */
 	unsigned int backlog;			/* force the frontend's listen backlog */