Map chair patch + other minor fixes

Patched map chair skill not disposing heal task properly in case of player changing maps while resting.

src/server/maps/MapleMap.java

@@ -2137,6 +2137,8 @@ public class MapleMap {
     */
 
     public void removePlayer(MapleCharacter chr) {
+        chr.unregisterChairBuff();
+        
         chrWLock.lock();
         try {
             removePartyMemberInternal(chr);