Apply clang format as proposed in T53211.
For details on usage and instructions for migrating branches
without conflicts, see:
https://wiki.blender.org/wiki/Tools/ClangFormat
This removes code duplication and put an end to the old "create at request"
batch creation.
Also it uses the same vbo as the uv layer used for shading. Reducing VRAM
usage.
Also fixes the modified uv display in uv edit mode.
Smooth round point with outline (uniform color) and fill (varying color).
Updated shader naming scheme: a shader that doesn't deal with color does not have to say "no color". Vertex shaders do not have to say "uniform color" since their frag counterpart actually has the uniform. Each name should describe what that shader *does*, not what it *doesn't do*.