issue #2460: add glfw include and library file to Xcode
issue #2460: glfw window version
issue #2460: glfw windows version: remove some unused function
issue #2460: rename EGLView::Create to EGLView->create
issue #2460: glfw mac version
issue #2460: glfw win32 project file
issue #2640: glfw linux version
Merge branch 'develop' into Iss2460-glfw-refractor

Conflicts:
	cocos2d_libs.xcodeproj/project.pbxproj
	cocos2dx/platform/mac/CCEGLView.mm
	samples/Cpp/TestCpp/proj.linux/main.cpp
	samples/Cpp/TestCpp/proj.win32/main.cpp
issue #2460: glfw mac keyboard input
issue #2460: glfw linux keyboard input
issue #2460: glfw windows keyboard input
issue #2460: optimize EGLView interface
issue #2460: remove comment code
issue #2460: travis scripts
issue #2460: script compile error
issue #2460: script compile error
issue #2460: change other sample projects to glfw version
issue #2460: project template for glfw
Remove the code of plugin.
Add plugin code as submodule