v0.4

Many, many changes:

• Nascent test suite
• Linting with Flake8
• CI with Travis
• Start of PyPI packaging (i.e., distribution via pip)
• Updated and more automated documentation and demos

And many more tiling types:

• SquareTri2Tessagon
• DodecaTriTessagon
• DissectedTriangleTessagon
• DissectedHexQuadTessagon
• DissectedHexTriTessagon
• PentaTessagon
• Penta2Tessagon