Pydarn

This major release includes:
- **NEW** IQ level data plotting
- **NEW** Latitude and longitude y-axis in RTP
- **NEW** Ball and stick plots
- **NEW** Map file variable time series plotting
- **NEW** Terminator plotting
- Coastlines available in magnetic coordinate spatial plots without Cartopy
- More flexibility in fan plots - single beams/ range gate range options
- TDiff correction for elevation data available
- Boxcar filtering available for data before plotting
- Corrections to geolocation algorithms
- Standardized plot return values across all plots
- **Bug fix** Radar position labels no longer overlap
- **Bug fix** Warning use refactored
- **Bug fix** Multiple bug fixes for data handling and plotting in grid plots
- **Bug fix** Multiple bug fixes for the aesthetics of convection maps

This patch release includes:

- **Bug fix** hdw repository installation issues resolved
- Inclusion of ICE and ICW in hdw repository and superdarn_radars module

pyDARN release v3.1 includes the following features:

- Full Cartopy coastline plotting options for all spatial plots
- *NEW* coastline keyword in method calls
- Full Cartopy integration for plotting in geographic coordinates for grid and fan plots
- Completed polar coordinate convection maps including reference vector and many customization options
- Improved ACF plotting
- New HALF_SLANT range estimation for RTP
- *Bug fix* Multiple fan plots now available on one axis
- *Bug fix* lowlat keyword now available for geographic coordinate plots
- *Bug fix* Colorbars now extend/don't extend as required along with many other minor improvements and bug fixes!

pyDARN release v3.0 includes the following features:
- **New** Optional *cartopy* integration for geographic coordinates and map underlays
- **New** Convection maps in magnetic coordinates
- Updates to use new format hardware files
- **New** `range_estimation` key word to give choice of range estimation techniques

**New Requirement**: pyDARN 2.2.1 requires minimum matplotlib version of 3.3.4

pyDARN release v2.2.1 includes the following features:
* Bug fix: fixed but in Summary plot not rendering
* Bug fix: fixed axes object not being properly handled in plot_fan
* Enhancement: Added `__version__` ability in pydarn
* Updated: citing warning printing on `import` instead of plotting
* Updated: pyDARNio 1.1.0 is requirement

**Deprecation**: `slant` option in `plot_range-time` and `plot_summary` is deprecated now uses `coords`

**New Requirement**: pyDARN 2.2 requires a minimum matplotlib version of 3.3.4

pyDARN release v2.2 includes the following features:
- **New** Radar geographical Field-of-View (FOV) calculations functionality
- **Deprecation** Removed FOV files for radars geographic beam location
- **New** pytesting environment for testing pydarn for development
- **New** FOV grid lines to show range gates
- **New** `channel` option in Fan plots
- Bugfix in Range-time plots with groundscatter
- Bugfix in Range-time plots with time-shifting

**Deprecation**: `slant` option in `plot_range-time` and `plot_summary` is deprecated now uses `coords`