Fix build from propagated changes in fcrepo4

Resolves: https://www.pivotaltracker.com/story/show/70398798
Add sonatype snapshots repo so fcrepo snapshots can be resolved

Resolves: https://www.pivotaltracker.com/story/show/69148052
Add authenticated access to Fedora repo.

Resolves: https://www.pivotaltracker.com/story/show/64929156