增强对事件订阅的管理，实现安全的自动反订阅
Merge branch 'master' of https://github.com/beyondlwm/FCEngine

Conflicts:
	FCEngine.vcxproj
	FCEngine.vcxproj.filters
	SourceCode/Event/CTouchDelegate.cpp
	SourceCode/Event/CTouchEvent.h
	SourceCode/Event/EventConnection.cpp
	SourceCode/Event/EventConnection.h
	SourceCode/Event/EventDispatcher.h
	SourceCode/GUI/Layout/GridLayout.cpp
	SourceCode/GUI/Layout/GridLayout.h
	SourceCode/GUI/Renderer/WindowRenderer.cpp
	SourceCode/GUI/Renderer/WindowRenderer.h
	SourceCode/GUI/WindowAttachPoint.cpp
	SourceCode/GUI/WindowAttachPoint.h
	SourceCode/Render/Viewport.cpp
	SourceCode/Render/Viewport.h