Refactor plotting into a separate module
Implement plotting of points
No need to make a new figure if one already exists
implement LineString plotting
Implement GeoDataFrame plotting in plotting module
Implement coloring polygons by values in column
Support for plotting categorical column data
Add option to draw legend for categorical data
Should plot a colorbar for non-categorical legend, not implemented yet
Merge pull request #7 from kjordahl/feature-plotting

Improvements to plotting