add plugin rest implementation
add fail tests
Merge branch 'develop' of github.com:caskdata/coopr into COOPR-526
update after review, change http handler
update  getPluginTypeMap method
Merge branch 'develop' of github.com:caskdata/coopr into COOPR-526

Conflicts:
	coopr-rest-client/src/main/java/co/cask/coopr/client/rest/PluginRestClient.java
COOPR-526: Fixed compilation error after merge.
fix delete resource method
fix delete resource method
COOPR-548: Added integration tests for Plugins Rest Client.
Merge pull request #717 from cybervisiontech/rest-client-integration-tests

COOPR-548 Plugins Rest client integration tests