Fixes the tanks' research bug from v2.4 and adds improved balance and some new content.
- authorization granted for using models from the terrific mod Battlefield 1918.
- 3d art: replaced my Whippet model by the one from BF1918, which is much better.
- 2d art: added custom textures for the Italian, Japanese and German Whippets.
- 3d art: new French light cavalry tank model, the Schneider CA1, from BF1918.
- code: removed the city Verdun and added Nanci to France, improving their industrial park.
- code: moved the city Kosice from Ruthenia to Slovakia.
- code: decreased IPUs of some Austro-Hungarian cities.
- code: equalized armies (increasing/decreasing troops of Russia, USSR, Romania, Serbia, Austria-Hungary, etc.).
- code: added some research technologies to countries.
- code: balance of IPUs for some researches.
- code: balance of aggressive behavior of some countries.
- code: edited historical countries.
- code: fixed the bug with the tank's research requirements.
