Test that all of the supported RDF response types work
Merge pull request #325 from cjcolvar/search-accept-rdfjson

Test that all of the supported RDF response types work

Resolves: https://www.pivotaltracker.com/story/show/71234752
Adding HTTP-based PID minter
Updating configuration, adding unit test
Adding support for authenticated PID minter services, extracting identifier from XML responses using XPath
Adding unit test to exercise xpath functionality
Using PoolingHttpClientConnectinoManager for pooled connections to remote PID minter
Making master.xml spring config file to bundle config files and avoid wildcard include, breaking out minter config and making it configurable with system property fcrepo.minter.config
Merge branch 'http-pid-minter' of github.com:fcrepo4/fcrepo4 into http-pid-minter
Using constructor arguments insted of setters