Make path configurable

include/config.h

@@ -53,6 +53,8 @@ struct Config {
         const char *terminal;
         const char *font;
 
+        const char *ipc_socket_path;
+
         /** The modifier which needs to be pressed in combination with your mouse
          * buttons to do things with floating windows (move, resize) */
         uint32_t floating_modifier;