Fix the issues with entvalidate.py
It doesn't properly handle mixins / special templates On python 3.8+, XML elements are no longer sorted and this fails validation against entity.rng mixins are not properly applied because the | split is incorrect (3 max items instead of 2) merge="" is not supported Parents aren't always passed when they should be. on windows it is incorrectly assumed that the encoding is 1252
Patch by: @baco
Tweaks by: @Stan
Based on a patch by: @wraitii
Differential Revision: https://code.wildfiregames.com/D4698