Configurable colors, add colorbar, code cleanup

See changes for 0.5. Thanks to @Ashafix and @H4dr1en for the PRs:

• Configurable colors
• Added colorbar
• code clean up

0.4

Lots of bug fixes but main improvement is drastically simplified install procedure for OS X and Windows, thanks to @gautamkarnik. Also, I merged @h4nyu's PR for remove hard coded fontname.

Add uni and bivariate feature space depictions

Regression univariate feature-target space

Regression bivariate feature-target space

Regression bivariate feature-target space heatmap

Classification univariate feature-target space

Classification bivariate feature-target space

Use simple node names to avoid issues with weird feature names

0.2.2

Fixes #6; use simple node name to avoid issues with weird feature names.

Fix windows compatibility issue

Just a tweak to fix path issue for windows. thanks to @Whamp.

make dtreeviz cross-platform

Enhancements:

• Squashed all commits prior to these updates to remove huge legacy files
• Works across mac, linux, windows 10. Only .svg output on linux, windows
• Leaf nodes respect class weights now in classifier trees, thanks to @dschoenleber
• SVG files on all platforms embed images for nodes, rather than linking to them. We had to do this with custom XML munging code, except on OS X where we can do -Tsvg:cairo on dot command
• Legend on classifiers now done with mathplotlib not graphviz

Initial (re-)release with decision tree visualization

I squashed commit history due to huge set of dead files. renamed from animl to detreeviz