Add #[name="..."] attribute for vertex format struct fields.
Add name attribute for shader params too.
Merge branch 'master' of git://github.com/gfx-rs/gfx-rs into vertex_field_name
Remove garbage comment.
Add #[name] attribute to test files.
Merge pull request #224 from KokaKiwi/vertex_field_name

Add variable name customizing ability.