Handle datastream updates correctly

- RdfRetriever uses HEAD to find descriptions of non-RDF resources
- Update dependencies so fcrepo-http-commons is test-scoped and required modules are explicitly included
- Add inject dependency for Elasticsearch build

Resolves: https://www.pivotaltracker.com/story/show/81198770
Use org.fcrepo.jms. as a header prefix rather than http://fedora.info/definitions/v4/repository#

Partial resolution of: https://www.pivotaltracker.com/story/show/81285766
accept fcr:transform responses as JSON arrays
Merge pull request #61 from acoburn/fcr_transform

accept fcr:transform responses as JSON arrays

Partial resolution to: https://www.pivotaltracker.com/story/show/81870262
Collapse #rest-api namespace into #repository
- Remove #rels-ext namespace

Partial resolution of: https://www.pivotaltracker.com/story/show/82075356
[maven-release-plugin] prepare release fcrepo-message-consumer-4.0.0-beta-04
[maven-release-plugin] prepare for next development iteration
Update site-maven-plugin version

Partial resolution of: https://www.pivotaltracker.com/story/show/82427854
Update minter package

Partial resolution of: https://www.pivotaltracker.com/story/show/82900612
Move FedoraJcrTypes to org.fcrepo.kernel package

Partial resolution of: https://www.pivotaltracker.com/story/show/83037816
Enable JcrXmlRetriever to follow describedby links

Resolves: https://www.pivotaltracker.com/story/show/83261280