Add GLSL language support #490

[sangsatori]

Logo is a mash-up of OpenGL and OpenGL ES logos.
All tests pass.

[spenserblack]

The primary colors from those two logos look pretty good combined IMO

[spenserblack]

@o2sh Any feedback before we merge this?

[o2sh]

Yes, sorry about the delay 😓 I'll try to find some time this week to review this PR.

The ASCII art could be cleaned/improved, IMO. I'll come back with a suggestion as soon as possible.

[o2sh]

Thanks a lot for your contribution @sangsatori and sorry for the late review.

I left a suggestion.

[spenserblack]

As a side-note, I wonder if we can update CONTRIBUTING.md to add some guidelines on authoring ASCII. Useful characters, how to round edges, opacity levels, stuff like that.

[o2sh]

I'm afraid that if we enforce guidelines for ASCII art creation, it could go against contributors' creativity and result in uniform-looking designs 🤔 . IMO, we should encourage contributors to express their creativity and come up with unique designs that complement the original logo.

Even it means making minor adjustments if necessary 😅