Beta 1.7.2 - Quest System Fixes

Another quick build to resolve a few issues related to the quest system.

• Fixed the bug that caused the cursed farm mist to remain even after finishing the quest. If your game is stuck in this state, loading your save with this build will also clean up the curse mist.
  
• Fixed a bug that caused the quest system to add quests to the added quest tracker (this decides what quests you can have) that were already added. This would result in having a TON of the same quest in the system. Removing this should also speed up saves a bit as the large quest list would take longer to save.
  
• Removed a couple of things from the save system related to quests that didn't need to be saved since the system rebuilds them from scratch every time you load a game. This should also speed up saving a bit.