py5 on mybinder, better OSX support, bug fixes

Release Highlights

• Fixed problems related to printing from Jupyter notebooks
• py5 now works well on mybinder
• Py5SketchPortal Widget, necessary for viewing animations on mybinder
• The IPython line magics such as %screenshot and %animatedgif are no longer magics and have been converted to regular functions in py5_tools
• Improve OSX support
• Lots of little bug fixes

Complete Docstrings + Bug fixes

Release Highlights:

• Complete, accurate, and truthful docstrings for every field and method in every py5 class
• Correctly support print statements in Sketch methods when using Jupyter lab
• Improve OSX support
• Lots of little bug fixes

Jupyter Notebook Kernel, Better OSX Support

Release Highlights:

• New Jupyter Notebook Kernel devoted to py5
• Better OSX support
• Many repairs to exiting docstrings, new docstrings for undocumented methods
• Many bug fixes, repairs to math functions