WIP started implementing gregorian interval calculations
Re-write of bucket calculations, removed old "calc_keys" in favor of
flexible bucket calculations, re-implemented calc_keys specifically for
redis.
WIP Implementing the harder features of gregorian dates and refactoring
Timeseries.series
WIP using the calculators to determine bucket ranges, and changing the
API to Timeseries.series() to support start and end timestamps
Implemented gregorian buckets() and unit tests
Documentation on gregorian intervals
Adding back support for weekly intervals with strptime workaround
Implemented handling of gregorian time configurations
WIP testing gregorian time
More tests for gregorian dates and new parameters to series()
Fixed mongo series implementation to return missing time intervals
Merge branch 'gregorian-intervals' of github.com:agoragames/kairos into gregorian-intervals