Update perforce SCMTool to use p4python 08.1 API.

Review Request #460 — Created July 23, 2008 and submitted — Latest diff uploaded

Information

Review Board SVN (deprecated)
trunk

Reviewers

As of the 08.1 API release, the p4python wrapper is now an officially supported
product from Perforce.  This is awesome, but they changed things up a bit
(entirely for the better -- parsing changesets is quite a bit simpler now).
This change updates our perforce tool to use the new API.
This code has been running on reviewboard.eng since they upgraded our main
perforce server a couple months ago.