Removes unversioned files from perforce repository. Script is in beta, though it works. It's a little slow due to the way fstat is used, but that will be changed soon, so the speed up should be enormous once that's done, up to 100x or more.
This script does parse __.p4ignore__ ignore files, compiles the fields as regex, and scans every directory and file against the local and parent __.p4ignore__ files. This is my first time doing something like this, and I just realized this isn't actually correct; I need to update how things are ignored to follow the [spec](http://www.perforce.com/perforce/r12.1/manuals/cmdref/env.P4IGNORE.html), since it's not straight up regex.
