Networking: Add keepalive packet for players, so that prediction doesn't break.

src/server/scihunt/client.c

@@ -58,6 +58,8 @@ void Game_PlayerPostThink(void)
 	player pl = (player)self;
 	Animation_PlayerUpdate();
 
+	pl.SendFlags = PLAYER_KEEPALIVE;
+
 	if (pl.old_modelindex != pl.modelindex)
 		pl.SendFlags |= PLAYER_MODELINDEX;
 	if (pl.old_origin[0] != pl.origin[0])

src/server/valve/client.c

@@ -68,6 +68,8 @@ Game_PlayerPostThink(void)
 	player pl = (player)self;
 	Animation_PlayerUpdate();
 
+	pl.SendFlags = PLAYER_KEEPALIVE;
+
 	if (pl.old_modelindex != pl.modelindex) {
 		pl.SendFlags |= PLAYER_MODELINDEX;
 	}

src/shared/entities.h

@@ -44,6 +44,7 @@ enumflags {
 };
 
 enumflags {
+	PLAYER_KEEPALIVE,
 	PLAYER_MODELINDEX,
 	PLAYER_ORIGIN,
 	PLAYER_ORIGIN_Z,