ChangChange all vertex shaders to accept model, view, projection
matrix to calculate the vertex position. So now we don't need to
convert the coordinates to OpenGL coordinate space [-1.0, 1.0]
anymore.

Additionally make it possible to offset vertex coordinates so
we can apply 0.5 px offset (to hit the pixel center) at some
operations.

Change-Id: I8e0a61d5fd4ab6aaa1c0c94439061725918577a0
(cherry picked from commit 2e99e4e1)
Reviewed-on: https://gerrit.libreoffice.org/16919Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>