Support mods with multiple script packages

[robojumper]

The extension requires mods to exist in Src/ and have a Classes folder for the source files. This means that the Classes folder is already where the X2/WotC setup would have copied the files, and:

• Src/MyOtherPackage/Classes/ sources would not be picked up
• MyOtherPackage, as it is listed in the mod's XComEngine.ini/XComEditor.ini, would not be even considered by the script compiler as a dependency (X2/WotC would copy the config to XComGame/Mods//Config and have the compiler load them at startup)

#1 may help with this.

[E3245]

Added via PR #19. It will read the mod's XComEngine.ini config and attempt to pull the packages from SDK/XComGame/Script into Game/XComGame/<WorkspaceName>/Scripts. RunMod() does not copy all files from the various Src folders yet.