#add New explicit constructors which append.
#add Move support for TSet::Append.
#add Move operators for TSetElement.
#change Some ranged-for loop changes.
#change Some existing code changed for testing (PluginManager, Subversion plugin).
#codereview robert.manuszewski,gareth.martin
[CL 2080362 by Steve Robb in Main branch]
- Added program-only plugin support and made UHT script plugin aware
- Added 3 generic script plugins with experimental Lua integration: ScriptGeneratorPlugin (UHT), ScriptPlugin (Engine), ScriptEditorPlugin (Editor-side)
- Lua integration is disabled by default
[CL 2058611 by Robert Manuszewski in Main branch]