Customizability features added to Phylo.draw

Features added based on https://redmine.open-bio.org/issues/3336.  Users now have the ability to input key word arguments representing pyplot options into plots they create to customize the plots.  Also, an option is added to the plotting code that allows clade lines to be created with matplotlib's linecollection objects enabling plot line customization.  Thanks to Lee at github.com/waterimp for his assistance including kwargs processing techniques and feedback on other code.

Co-authored-by: Lee Bush <github@waterimp.com>