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Added
1) Docs and gallery added.
2) Added option to change the penalty and center spot size via spot_scale.
3) Added legend handlers for plotting footballs in the scatter method, arrows in the arrows method, and lines in the lines method of the Pitch class.
Changed
1) utils module renamed scatterutils
2) Pitch.quiver() renamed Pitch.arrows()
3) Default color of Pitch.lines() changed to rcparams['lines.color']
4) Default hexbin cmap changed to viridis
5) Pitch.lines() now takes alpha_start and alpha_end arguments. The line linearly increases in opacity from alpha_start to alpha_end if transparent=True. Previously these were hard coded as 0.1 and 0.5. The new defaults are 0.01 and 1.
6) Pitch.lines() not takes cmap as an argument. You can either select cmap or color, but not both.
7) Pitch.bin_statistic_positional() and Pitch.bin_statistic() return dictionaries rather than named tuples.
8) Pitch defaults changed to tight_layout=True and constrained_layout=False.
9) Default penalty and center spot size now smaller and can be adjusted.
10) Pitch default colors changed, pitch_color is now not plotted by default ('None') and pitch lines are taken from the rcParams 'grid.color'.