>= saucy on kernel 3.4 and non-Atom Intel, downgrade mesa to version 8 (precise)

Discussed extensively in #704.

The tricky part is that `libegl1-mesa-drivers` was split in 2 parts, so there is a new `libwayland-egl1` package (required by kde). We create a fake package with `equivs` to work around that.

Tested in `2014-07-06_10-19-56_drinkcat_chroagh_x11test.tmp-pin-3.4-drivers_-R_precise-saucy-trusty_35`, output is here:
http://drinkcat.github.io/chroagh/2014-07-06_10-19-56_drinkcat_chroagh_x11test.tmp-pin-3.4-drivers_-R_precise-saucy-trusty_35.html
(3D acceleration is working on all platforms and Ubuntu releases)

@DennisLfromGA, @peter-gulka: Could you test this branch? In particular, I'm interested in KDE and Steam (testing Gnome, Unity, XFCE would be good too).
You can fetch the branch here: https://github.com/drinkcat/chroagh/archive/pin-3.4-drivers.zip, then extract and run `sudo sh installer/main.sh -n chrootname -u`
Do we need all three of these, or do the updates or security repos effectively supersede the main repo for our needs?  Adding another entire release to apt is pretty heavyweight and slows down the update process a lot...