TODO

Before 0.3.0:
•Save a checkpoint file at each stage of the conversion ✓
•Read checkpoint files ✓
•Resume a conversion from a checkpoint file ✓
•Replace saving TIN and DXF files at each stage with export actions ✓

Before 0.4.0:
•Get rid of spikes that the program hallucinates in areas with no dots ✓

Before 0.4.1:
•Export in PLY format ✓

Before 0.5.0:
•Split large matrix operations among threads when only one thread is trying to do a rowop or triop ✓

Before 1.0.0:
•Draw contours, removing wiggles as long as they don't violate the accuracy requirement ✓
•Export contours in DXF ✓

Whenever:
•Color the triangles of the TIN in PLY format to show which triangles are empty, even if empty triangles are exported, and which have dots out of tolerance (Points, not triangles, are colored in 0.5.1, and it does not indicate dots out of tolerance.)
•Add a magnification window
•Switch to a list of triangles and edges to be checked when most of them are in tolerance ✓
•Draw a scale on the window ✓
•Search directory for unfinished conversions and resume one
•Allow the TIN to follow the highest points or the lowest points instead of the average