cvitolo/rnrfa: rnrfa v2.0.2

Major changes:

1. Fixed issue #19 whereby rejected/missing data in peak flows are flagged as such in output. Added full_info to input parameters to retrieve data quality flags.
2. timeseries are now classed as zoo object, not xts.
3. startseason and endseason in seasonal_averages() are now deprecated, seasons are labelled by the calendar quarter in which the season ends.
4. Removed obsolete tests that were checking against proj4-based pre-calculated values. This is to overcome issue with use of proj6.

Minor changes:

• Added more tests