WP8 Shader fix for cocos2d-x issue 8933

This pull request fixes cocos2d-x issue https://github.com/cocos2d/cocos2d-x/issues/8933 

It appears that the ccShader_Label_df.frag and ccShader_Label_df_glow.frag shaders will crash some older Windows Phones such as the Huawei W1, I disabled these shaders (and the use of these shaders) and now apps  launch and run fine on the older WP8 phones.

Minor compiler warnings in WP8 code were fixed.

Added use of lock free concurrent_queue to improve input event performance 


Got it.