add: add current map and current time to graph editing overlay

fix: send client messages as unreliable to prevent reliable channel overflow (should solve problems when editing large number of waypoints on single location)

inc/support.h

@@ -112,6 +112,9 @@ public:
    // checks if same model ommiting the models directory
    bool isModel (const edict_t *ent, StringRef model);
 
+   // get the current date and time as string
+   String getCurrentDateTime ();
+
 public:
 
    // re-show welcome after changelevel ?