enable batching of paths

[bsalomon, 2012-03-13 21:23:20]

This will require a rebaseline of filltypespersp_gpu. I don't really understand
why. The pixel changes seem gpu/driver dependent and are small in number and
value:

0 on windows z600
1 pixel on linux z600  (max intensity: 2)
1 pixel on MBP 10.7 with NV 330 (max intensity: 2)
7 pixels on MacPro 10.6 with ATI 5770 (max intensity: 3)

On all the above machines I compared complete GM runs pre- and post-change and
only this test changes.

The image attached to this review is from the MacPro run.

[TomH, 2012-03-14 13:11:07]

LGTM

[bsalomon, 2012-03-15 12:32:41]

Closed with r3382