Added Agent Cap for Empire engineer units

TODO:
Add unit cap for Dragon Slayer (Dwarf)

Fixed an issue where a skill for Elspeth was missing a description

Switched growth effect to match new Vanilla standards

Added combat skills for Empire Master Engineer lords (first pass on balance, visuals are placeholders)
Added skills to Epidemius (Nurgle)

---- TODO ----
Add combat skills for Malakai
Find better visuals for Empire Master Engineer Skills

Adjusted columns from 500 -> 30 to account for display changes with the latest patch (will create more incompatibilities with other skill mods in future, but the patch has put us in a bind here)

---- TO DO ----
Malakai Combat Skill Line
Master Engineer Combat Skill Line

Column change test (the devs seem to have done something naughty here)

Updated for new DLC

---- Currently missing the following content ----
Malakai Combat Skill Line
Elspeth Skills
Tamurkhan Skills
Master Engineer Combat Skill Line

Fixed an issue where the empire's upkeep was being increased instead of decreased

Fixed an issue where Nakai's Kroxigors were missing skills

Fixed an issue where High Elf skill "Efficient Planning" was not behaving as expected

Resolved an issue with a bad effect scope setting causing problems in multiplayer games