Updated series of weston patches.

[Mario Kleiner]

A resend of my series of patches, now with reviewed-by of Derek Foreman
for some of the patches, and the other patches updated to take Derek's
and Pekka's feedback and suggestions into account. Numbering of patches
is a bit scrambled wrt. the original series.

Patches 1, 2 Reviewed by Derek - Thanks.

Patch 3 waiting for feedback. Would be helpful to have this unintrusive
patch to simplify testing of timing and other low level stuff with special
hardware measurement equipment.

Patch 4,5 Split up original patch into two separate patches, and
modified according ot Derek's review feedback.

Patch 6,7,8: Split into separate patches and implemented
Pekka's suggestions for improvements.

Patch 9 Added a new test to presentation-shm demo to allow
better testing of patches 7+8, as suggested by Pekka.

Thanks,
-mario