Add glActiveShaderProgram and direct glUniform* to right program
Add glClampColor and glReadnPixels

* glClampColor doesn't have to be serialised as it only affects
  glReadPixels (which aren't serialised).
Implement glInvalidate* just by marking resource as GPU dirty
Add 2D multisampled array texture storage functions.
Add some missing hooked gl state functions

* glClipControl, glProvokingVertex, glPrimitiveRestartIndex,
  glDepthRangeIndexed, glClearDepthf
Implement glDrawRangeElementsBaseVertex
Implement glFramebfuferParameteri