Snap windows and rename entries

[Falki-git]

• Added window snapping (can be turned off in settings)
• Added renaming of individual entries by user
• Converted Manager, UI and MessageManager to singletons
• Add support for SpaceWarp 1.2.0 (mod_id discontinued in favor of BepInEx GUID); backward compatibility with SW 1.1.x retained
• Updated readme screenshot