performance: Don't autoupdate multiplayer games more than a week old - they're inactive games

performance: Don't calc checksum for non-multiplayer games, no one cares if you hack your own game

tests: Load vanilla game test fixed

Buildings missing from ruleset are removed from loaded games *properly*

chore: Added missing imports

chore: Reorg tests, so /testing folder contains only test-helper classes

By SomeTroglodyte:
- Fix Map Editor double map holders after ruleset change 
- Fix longpress triggering when an onClick discards its actor 
- Improve BaseUnit hasUnique(FoundCity) handling 
- Fix Gdx not forced to UTF-8 when saving a game 

Defensive pact notification fix  - By tuvus