Fix potential crash after loading of saved game (#242, #266)

When number of edicts parsed from saved game is smaller than `sv.num_edicts`, "old" edicts are not freed nor unlinked while their memory can be reused by newly spawned entities

(adapted from sezero#75)

Quake/host_cmd.c

@@ -2653,6 +2653,10 @@ static void Host_Loadgame_f (void)
 		entnum++;
 	}
 
+	// Free edicts allocated during map loading but no longer used after restoring saved game state
+	for (i = entnum; i < qcvm->num_edicts; i++)
+		ED_Free (EDICT_NUM (i));
+
 	qcvm->num_edicts = entnum;
 	qcvm->time = time;
 	sv.autosave.time = time;