Better GLSL support

Describe your feature request
I would like syntax highlighting for GLSL to make it easier to read (and write/mainitain) GLSL code.

What problem(s) would this feature solve?
Writing code in GLSL (e.g. for WebGL or OpenGL).

Explain what you were trying to do when you came across the problem leading to this feature request
Writing shaders in GLSL (for a website using WebGL).