gsdx: openglES fix

* require a 3.1 context
* unattach texture of the fbo when they're not used
(avoid to have a texture and depth_stencil with different size)

Note: except minor shader bug it works on Nvidia 340.23.01
gsdx-ogl: disable texture compare mode

It seems to be used for depth texture
i10n: update th_TH mo file