Catch SCMErrors in repository resource.
Review Request #3168 — Created July 1, 2012 and submitted
Catch SCMErrors in repository resource. When RepositoryResaurce._check_repository would encounter an SCMError, it would just blindly throw the exception up higher, returning a bare 500 error to the client. It's not unexpected that we might hit SCMError, so here we go: return it to the client as REPO_INFO_ERROR.
