Login tokens

Ping @TomRK1089, can you take a look please? I used git-hg to fork your Google Code project so that I could hack on this here. I've added support for login tokens so that we can continue to use j2bugzilla with our upgraded Bugzilla install (4.2 -> 4.4.4). Login cookies are no longer supported by Bugzilla. See commit message for more info please.