enum class for ProgressTimer::type
enum class for LanguageType, Application::Platform
Platform::LINUX --> Platform::OS_LINUX, Platform::ANDROID --> Platform::OS_ANDROID. ANDROID is defined by ndk.
issue #2430: Refactoring enum 'ResolutionPolicy'.
issue #2430: Fixing a typo.
Merge branch 'develop' of https://github.com/cocos2d/cocos2d-x into constants-refactor

Conflicts:
	scripting/lua/cocos2dx_support/LuaCocos2d.cpp
Updating LuaCocos2d.cpp
ResolutionPolicy::EXACTFIT --> ResolutionPolicy::EXACT_FIT
Application::Platform::OS_MACOS --> Application::Platform::OS_MAC.
Merge pull request #3276 from dumganhar/constants-refactor

Enumeration refactoring