allow players to disable certain screens

This commit does several things:
	1. creates a "Simply Love Options" in the operator menu
	2. moves FailSet and NumberOfContinuesAllowed to that
	3. creates 3 new custom options for disabling EvalSummary, NameEntry, and GameOver
	4. fixes/changes my use of ThemePrefs (booleans kept resetting?) rely on numerics instead of booleans
	5. adds some small checks to see if the Simply Love ThemePrefs section exists (if it doesn't, create it) and if ThemePrefs types need to be updated (see #4 above!)