Merge pull request #183 from avalonmediasystem/hotfix/gem-locking

Lock hydra-head and devise (-> master)
Reading for r3
Allow delete to complete even when derivative retraction fails
Merge pull request #300 from avalonmediasystem/bugfix/derivative-deletion

Skip derivative retraction if workflow id missing
Add missing license headers
Add missing license headers to views
Merge pull request #301 from avalonmediasystem/r3-license-headers

R3 license headers
Bump default branch in capistrano deploys
Merge pull request #303 from avalonmediasystem/release/3.0.0

Release/3.0.0
Merge pull request #304 from avalonmediasystem/master

Merge 3.0.0 back into develop