add fragment shaders
new shader test code
Merge branch 'develop' into new_shader_test
issue #2782: update mac version, update test case title
issue #2782: shadertestSprite android make file
issue #2782: remove a blank test case
issue #2782: shadertestSprite linux and windows version
issue #2782: shadertestSprite change test case textures and add normal sprite for comparison
Merge pull request #3571 from dabingnn/new_shader_test

issue #2782 shader test sprite