Added Github + Discord icon links on main menu

City construction progress is reset when puppeting, not when annexing

Mods:
- Allow loading games where a buildings' "replaces" has been removed
- Allow loading games with natural wonders that have been removed from mods
- Only add city ruins improvements if they exist in the ruleset

Added lake-land edge tiles - by legacymtgsalvationuser69544

Move Capital building function from city to civ  - By SeventhM