improve debug message for shader compilatione errors

Change-Id: I14106870bd46c081a574d28f416278b848544fcc
seems like the better approach for getting it working

Change-Id: I18d5ecc9a14a6eb8ad8c6ea5ec9835dbe8f5db40
fix OSX check for GL_EXT_texture_array

For some reason the extension is supported in GL but not in GLSL.

Change-Id: I1cad8baea23e80714269454af23fca87ea9e2949