Added POST/PUT support for the default channel

Conflicts:
	flows/mediation/defaultchannel.mflow
	src/main/resources/defaultchannel-mapping.json
Added integration tests for testing default channel put and post

Conflicts:
	src/test/resources/integration-tests/OpenHIM-integration-tests.xml
Added integration tests for testing default channel put and post

Conflicts:
	src/test/resources/integration-tests/OpenHIM-integration-tests.xml
Re-added default channel from merges