Fixed issue where the list of previous saves on the save puzzle prompt was not showing Custom Puzzle saves.

Also added in a feature that will now search the save directory on startup for any missing saves in the list of saved games file. The game has separate save files for each puzzle and room but also a file that keeps a list of all of these saves. In case the list gets corrupted this can refresh the list.

One nice side effect of this is now you should be able to share save game files with other people. For instance room saves have the prefix "rm_". Copying a room save to:

C:\Users\USERNAME\AppData\Local\Jigsaw\Saved\SaveGames

will add that room design to your list of rooms. Something at least until I can get workshop support for custom rooms.