Fix shader file loading for oF < 0.8.1
Merge pull request #25 from OliverUv/fix-legacy-shaderload

Fix shader file loading for oF < 0.8.1
ofxBokeh GL3 support
Merge pull request #26 from OliverUv/ofxBokeh-gl3

ofxBokeh GL3 support
Fix to Compile for TARGET_OPENGLES
Initial OpenGLES ES2 shader test - Working
ES2 Example Project (iOS only for now).