Fixed a bug where SGFs would be saved and loaded mirrored, which meant that outside SGF files would be loaded in incorrectly.

Fixed a bug where the hash would not update when states were reverted, thus preventing the user from making the same moves again.

New Features

• ability to save board states
• ability to return to previously saved board states
• ability to save game tree as SGF
• ability to save entire game, including states, in a JSON savefile
• ability to load JSON savefile and restore game tree and saved states