Renaming of CCWindow:ActiveDirector to DefaultDirector
Renaming of CCWindow:ActiveDirector to DefaultDirector

* a window can have multiple running directors, so rename removes ambiguity as to whether ActiveDirector represents only running director

haithemaraissia/CocosSharp,netonjm/CocosSharp,zmaruo/CocosSharp,MSylvia/CocosSharp,hig-ag/CocosSharp,hig-ag/CocosSharp,haithemaraissia/CocosSharp,MSylvia/CocosSharp,TukekeSoft/CocosSharp,TukekeSoft/CocosSharp,mono/CocosSharp,zmaruo/CocosSharp,netonjm/CocosSharp,mono/CocosSharp