Fix detekt by using fully qualified import

Resolved ANRs on new game screen when user has a lot of maps, by deferring the parsing of most of the map files until after the screen has loaded

Fixed errors when cloning civ that should open policy picker

4.7.17-patch1

By SeventhM:
- Fix promotions being available when they shouldn't 
- Allow buildings to require population, Allow buildings to use condtionals 
- Add Improvements to the list of of known improvement filters 
- Refactor: Remove unnecessary ruleset checks 

By SomeTroglodyte:
- Fix Permanent Audiovisual toggle and start on declarative Mod Compatibility 
- Linting of unused new function shouldOpenPolicyPicker() 

By tuvus:
- Ai nuke improvement 
- AI now move units closer to enemy first in wartime 
- Improved AI chooseAttackTarget 
- Changed defensive pact description 

Add tests for city class and introduce small refactor  - By Framonti