[OSM-dev] Simplifying ways

[Paul Norman]

I'm working with a process where I generate a .osm file and need to simplify
the ways in output on the command line. JOSM's simplify way command isn't an
option as it requires interaction and it is also fairly slow on large files.
Using ogr2ogr to simplify the source files is not an option as it could
cause the different layers to no longer agree with each other.

I'd rather not re-implement Douglas-Peucker if someone has already done it.