Added OpenGLCommon unit, with rendering code that is common to both desktop and ES versions of OpenGL
Added OpenGLCommon unit, with rendering code that is common to both desktop and ES versions of OpenGL

auokss/TERRA-Engine,Relfos/TERRA-Engine,auokss/TERRA-Engine,thecocce/TERRA-Engine,thecocce/TERRA-Engine,Relfos/TERRA-Engine,Relfos/TERRA-Engine,Relfos/TERRA-Engine,thecocce/TERRA-Engine,Relfos/TERRA-Engine,thecocce/TERRA-Engine,thecocce/TERRA-Engine,Relfos/TERRA-Engine,auokss/TERRA-Engine,thecocce/TERRA-Engine,Relfos/TERRA-Engine,auokss/TERRA-Engine,thecocce/TERRA-Engine