Docserver: update handlebar.

Docserver: update third_party/handlebar. handlebar.py (used in the docserver) now has much
faster rendering (about 3x improvement) and parsing (about 2x improvement).
This halves the runtime of the integration/cron tests as well as making page load snappier.

NOTRY=true

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=200687

[not at google - send to devlin, 2013-05-16 23:02:35]

Hey Clark,

CL description is brief because I have to run, but this updates to the new
handlebar. About 3x rendering speed improvement, 2x compilation speed. Feel free
to review the handlebar python if you want.

[cduvall, 2013-05-17 01:05:47]

lgtm. Yay speed increase! I looked over the handlebar code, but not super
closely.

[commit-bot: I haz the power, 2013-05-17 01:35:35]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/kalman@chromium.org/14693006/1

[commit-bot: I haz the power, 2013-05-17 01:40:19]

Change committed as 200687