accurev provider

[ggardner]

Hi all, 

I've been working on extending the AccuRev provider implementation to be
fully compatible with the maven release plugin. 
(ie update, status, checkin, tag, checkout, add)

I think I'm pretty close with the necessary commands implemented and the
tck tests passing against an AccuRev evaluation install.

Assuming someone here is interested I'll have a bunch of questions about
how I might go about contributing this code.

Cheers,
     Grant.