Add yes-no dialog and general dialog code to present choices to players. Can be used by triggers.

git-svn-id: http://svn.wildfiregames.com/public/ps/trunk@15480 3db68df2-c116-0410-a063-a993310a9797
Forward-declare CShaderProgramPtr, to avoid pulling in more headers than necessary and to hypothetically reduce build times by a minuscule amount.


git-svn-id: http://svn.wildfiregames.com/public/ps/trunk@15481 3db68df2-c116-0410-a063-a993310a9797
Make CGUIManager register a callback function for hotloading instead of specifically calling it.

git-svn-id: http://svn.wildfiregames.com/public/ps/trunk@15482 3db68df2-c116-0410-a063-a993310a9797
Merge 'remotes/trunk'