performance:  - Don't need to always create hashsets, don't need linked hash set

performance:  - Only check promotion circular references once, not once per promotion

performance:  - Cache unique parameter validity for the same ruleset

performance: Only build strings in ruleset validation when necessary

Added unitTypes json schema

Added techs json schema

Added tileImprovement json schema

Added nations json schema

description testing on vscode showed we should remove pattern descriptions

Added link to unique list :D

Added descriptions for some fields

Double patterns for uniques, for square brackets as well

Added pattern to uniques to catch bugs

civilopediaText.json array-ized, since it's common *as an array*

Added units.json and separate schemas for uniques and civilopediaText, for sharing

specialistSlots and greatPersonPoints are specifically maps to numbers

Buildings schema references stats schema, so it's reusable from other places

Documentation: Validate json using online tool

Documentation: Validate json using online tool

update documentation since latest schema works on both!

Add stats as separate schema

Remove anyOf, because technically it requires matching all subschemas - just redeclare the stats values...

Consistent indendation

Instructions for setting up schemas on Visual Studio

Instructions for setting up schemas on AS

Better schema for checking field names

Test - Added building schema.json to docs

4.8.7-google-play

By tuvus:
- AI Open Borders Offer fix 
- Fix Nuke Notification 

Fix City construction context menu changing Puppets  - By SomeTroglodyte