Add 'get server <backend>/<request>' runtime api

Change-Id: Idc57f080703b5da7e6dac96874d20e2abf99e609
diff --git a/include/haproxy/backend.h b/include/haproxy/backend.h
index 8a763bf..0e2d75f 100644
--- a/include/haproxy/backend.h
+++ b/include/haproxy/backend.h
@@ -48,6 +48,7 @@
 void recount_servers(struct proxy *px);
 void update_backend_weight(struct proxy *px);
 int be_lastsession(const struct proxy *be);
+struct server *get_server_uh(struct proxy *px, char *uri, int uri_len, const struct server *avoid);
 
 /* Returns number of usable servers in backend */
 static inline int be_usable_srv(struct proxy *be)