Partitioned databases

[smithsz]

Checklist

• [x] Tick to sign-off your agreement to the Developer Certificate of Origin (DCO) 1.1
• [x] Added tests for code changes or test/build only changes
• [x] Updated the change log file (CHANGES.md|CHANGELOG.md) or test/build only changes
• [x] Completed the PR template below:

Description

Adds partitioned database support.

Approach

Inject _partition/<partitionKey> into the request URI when a partition key is specified for the following operations:

• All docs.
• View queries.
• Search queries.
• Find queries.

Also, adds an additional method on the database class to fetch database partition metadata.

Schema & API Changes

No breaking API changes.

New API:

• CloudantClient.createPartitionedDB(String dbName)
• Database.query(String partitionKey, String query, final Class<T> classOfT)
• Database.search(String partitionKey, String searchIndexId)
• Database.partitionInfo(String partitionKey)

Security and Privacy

No change.

Testing

Added additional tests:

• PartitionedDatabaseTest.java: Exercises the new partition querying features against a real Cloudant instance.
• PartitionInfoMockTests.java: Verifies mock partition metadata can be correctly deserialised.

Monitoring and Logging

No change.