don't crash the asset browser when loading sprites with 1 frame

closes #4125
StyleCop
harden asset browser against invalid user input and allow R8

closes #3980
abbreviate the user support folder as in mod.yaml
added a palette chooser and colorpicker dropdown to the browser
fixed index outside bounds of the array when 0 productions left

closes #4137
PaulCop clean
additional checks to avoid giving dead actors a rank sign

closes #4134
.IsDead() includes the .Destroyed check
updated CHANGELOG
Move RASpecialPowers into OpenRA.Mods.RA.Scripting
Add LuaInterface project
Add FindType method to ObjectCreator
Add map scripting support
Add LuaInterface dependencies
Update build, package and installer scripts for LuaInterface
install the Lua libraries on Mac OS and Linux
remove old and misleading note
moved KDE stuff into local git ignore
we now have .so and .dylib