Let TimeSeries implement Closeable.
Finished database implementation.
Updated documentation.
Close storage when closing a time series via database.
Disable flaky test for now.
Reflect API changes.
Fixed leaking close.
Reduced logging level.
Fixed double cleanup.
Added some test.
Added comment.
Fixed test.
Each window now has a dedicated Storage instance.
Fixed NPE.
Added tests for Db#getReaders.
Added extra test around granularity.
Improved documentation.
Clarified/fixed non-concurrent multi thread access.
Fixed Poller implementation.
Cleanup.