UI: Mod checker tab aligns mods

Modding:
- Units from triggers respect "limited to [amount] per civilization"
- Added notification for several unit triggers
- 'upon being defeated' applies to destroyed civilians as well

By SomeTroglodyte:
- Show garrison in City overview
- Harden and improve "Download Mod from Url" parser
- Future tech fix

By Gualdimar:
- Trade ending notification
- Fixed popup positioning after changing screen orientation

Improved Minimap colors  - By Caballero-Arepa