Added glBufferSubData, glDeleteShader, and glDetachShader
Added glUniform{1f,2f,3f,4f}
Added glFrontFace, and GL_CW/GL_CCW consts
Added glCullFace and its mode consts
Added EnableCap consts
Merge pull request #4 from sethpink/more_funcs

Added various missing functions/constants