* First attempt at porting Paul Mach's Visvalingam implementation
* Make indent
* Mostly working
* Approximate equivalence from Douglas-Peucker to Visvalingam levels
* Don't simplify away tile boundary crossing points
* Add a command-line option and test for Visvalingam simplification
* Update changelog
* Cleanup in response to review feedback
* Include <stdio.h> to fix compiler warnings
