Many performance improvements!

By SomeTroglodyte: 
- Support for languages using Diacritics (e.g. Bangla)  

By tuvus:
- Improved unit automation for defending cities 
- Warmongering doesn't apply to civs that are angry at the target civ 

Optimize screen orientation  - By HChenX - *NEW CONTRIBUTOR!*

AI behaviour changes  - By EmperorPinguin - *NEW CONTRIBUTOR!*