More Survival Guide sections (VSS, Perforce)

[Ian Clatworthy]

Some days I love my job more than others. Days when community members
submit documentation enhancements for me to review and merge are really
great ones in my book! Today's doc improvements are to the Survival
Guide and Data Migration Guide:

* Bazaar for VSS Users (Adrian Wilkins)
* Bazar for Perforce Users (Matt McClure)

Adrian also improved the tips on how to migrate from VSS to Bazaar.
Thanks guys!

If you want to make my day better, there's still plenty of opportunities
left. :-) If particular, the following need love:

* Bazaar for Git Users
* Bazaar for BitKeeper Users
* Bazaar for GNU Arch Users.

Also:

* Bazaar on Git Projects
* Bazaar on Mercurial Projects

See
http://doc.bazaar-vcs.org/migration/en/improving-these-documents.html if
you're able to help.

Ian C.