COMPMID-557 Added some GLES documentation and rework following OOB testing

Change-Id: I56333ed23d30c5ec3094f64b78a023589064fe06
Reviewed-on: https://eu-gerrit-1.euhpc.arm.com/113375
Tested-by: BSG Visual Compute Jenkins server to access repositories on http://mpd-gerrit.cambridge.arm.com <bsgcomp@arm.com>
Reviewed-by: Jim He <jim.he@arm.com>
Reviewed-by: Anthony Barbier <anthony.barbier@arm.com>
24 files changed