Migrate to using Uniform Buffer Objects (UBOs)

[jellysquid3]

Sodium (for historical reasons) still uses uniform variables. We should replace these usages with uniform buffer objects, which have a number of advantages:

• Dead code elimination in the shader compiler will not remove variables from buffer block declarations. This makes modifying shaders much less error prone and simplifies the shader program interfaces in Java.
• Using a streaming buffer to copy memory from the host to device is faster and involves fewer OpenGL function calls.