add test cases

[luizbarboza]

• [x] mfogel/polygon-clipping#75
• [x] mfogel/polygon-clipping#83
• [x] mfogel/polygon-clipping#86
• [x] mfogel/polygon-clipping#90
• [x] mfogel/polygon-clipping#91
• [x] mfogel/polygon-clipping#93
• [x] mfogel/polygon-clipping#94
• [x] mfogel/polygon-clipping#95
• [x] mfogel/polygon-clipping#96
• [x] mfogel/polygon-clipping#98
• [x] mfogel/polygon-clipping#101
• [x] mfogel/polygon-clipping#105
• [x] mfogel/polygon-clipping#111
• [x] mfogel/polygon-clipping#115
• [x] mfogel/polygon-clipping#118
• [x] mfogel/polygon-clipping#122
• [x] mfogel/polygon-clipping#124
• [x] mfogel/polygon-clipping#129
• [x] mfogel/polygon-clipping#139
• [x] mfogel/polygon-clipping#140
• [x] mfogel/polygon-clipping#141
• [x] mfogel/polygon-clipping#142

[Peque]

@SBanksX Did you run any performance tests after fixing all those floating point issues? I'd be interested in knowing how this implementation compares to https://github.com/mfogel/polygon-clipping.

Of course I can run the tests myself, but I am guessing there is a high chance you run them already while or after implementing the changes. :blush:

[markstos]

@Peque Many of the tests come from the polygon-clipping library, which crashes on the test cases, so it doesn't matter if polygon-clipping is faster if it doesn't work.