Merge pull request #11 from chids/IDE-setup-docs

Explicitly mention Lombok and how to generate Eclipse and IDE conf.
Add a thanks section to the README.
Add KV list, relation delete, and KV purge operations to the client.

Closes #6 and #7 and #8 and #9 and #10.
Update version to the next development iteration.
Add basic, and failing, unit tests for RelationFetchOperation.fromResponse()
Use JsonNode.path(String) which returns MissingNode instead of null
to eliminate two NPE's. Makes RelationFetchOperationTest.jsonIsEmpty
pass.
Extract JSON parsing from RelationFetchOperation.fromResponse() to
parry JsonMappingException.
Makes RelationFetchOperationTest.jsonIsIsBlank pass.
Refactor RelationFetchOperation.parseJson to handle null.
Makes RelationFetchOperationTest.jsonIsNull pass.
for-each > while
Add integration test for list operations
Proper seperation of query parameters when executing list operations
Merge pull request #16 from hnrc/fix-list-with-offset

Fix KvListOperation with {start,after}Key offset
Update the user guide and README for the 0.2.0 release. Merged #17.
Merge pull request #15 from chids/fetching-non-existant-relation-causes-npe

Fetching non existant relation causes NPE
Add @hnrc to the contributors section in the README.
Update the README for the '0.2.1' release.
Let Client implement AutoCloseable and rename stop() to close() so
that instances can be used in try-with-resources.