Merge pull request #119 from pv/quickstart

ENH: Add an easy way to quickstart the development environment
BUG: rest_comments: more robust working dir initialization

The initialization is done when it is needed, rather than at import
time, which avoids problems. Cleaned up code, too.
ENH: submission: show most recent revisions only in tag view
ENH: person: Tell search engines not to index user profile pages
BUG: submissions: respect is_displayed in Revision.objects.most_recent()
BUG: filestorage: fix invalid usage of repo.add
BUG: filestorage/dvcs_wrapper: make it raise understandable errors on DVCS failures rather than returning garbage
BUG: filestorage/dvcs_wrapper: set home directory, to avoid using invalid hgrc/gitconfig files