MINOR: server: add a list of safe, already reused idle connections

These ones are considered safe as they have already been reused.
They will be useful in "aggressive" and "always" http-reuse modes
in order to place the first request of a connection with the least
risk.
diff --git a/include/types/server.h b/include/types/server.h
index 411ea4b..cbeead9 100644
--- a/include/types/server.h
+++ b/include/types/server.h
@@ -168,6 +168,7 @@
 	struct list actconns;			/* active connections */
 	struct list priv_conns;			/* private idle connections attached to stream interfaces */
 	struct list idle_conns;			/* sharable idle connections attached or not to a stream interface */
+	struct list safe_conns;			/* safe idle connections attached to stream interfaces, shared */
 	struct task *warmup;                    /* the task dedicated to the warmup when slowstart is set */
 
 	struct conn_src conn_src;               /* connection source settings */
diff --git a/src/hlua.c b/src/hlua.c
index df3904f..6789351 100644
--- a/src/hlua.c
+++ b/src/hlua.c
@@ -5062,6 +5062,7 @@
 	LIST_INIT(&socket_tcp.pendconns);
 	LIST_INIT(&socket_tcp.priv_conns);
 	LIST_INIT(&socket_tcp.idle_conns);
+	LIST_INIT(&socket_tcp.safe_conns);
 	socket_tcp.state = SRV_ST_RUNNING; /* early server setup */
 	socket_tcp.last_change = 0;
 	socket_tcp.id = "LUA-TCP-CONN";
@@ -5107,6 +5108,7 @@
 	LIST_INIT(&socket_ssl.pendconns);
 	LIST_INIT(&socket_ssl.priv_conns);
 	LIST_INIT(&socket_ssl.idle_conns);
+	LIST_INIT(&socket_ssl.safe_conns);
 	socket_ssl.state = SRV_ST_RUNNING; /* early server setup */
 	socket_ssl.last_change = 0;
 	socket_ssl.id = "LUA-SSL-CONN";
diff --git a/src/server.c b/src/server.c
index e33f686..b7a498c 100644
--- a/src/server.c
+++ b/src/server.c
@@ -888,6 +888,7 @@
 			LIST_INIT(&newsrv->pendconns);
 			LIST_INIT(&newsrv->priv_conns);
 			LIST_INIT(&newsrv->idle_conns);
+			LIST_INIT(&newsrv->safe_conns);
 			do_check = 0;
 			do_agent = 0;
 			newsrv->flags = 0;