Various fixes, cleanups and optimizations

- gitignores
- Fixes from testing, regarding communication
- Typewheel rotation should work now
- cleanup of greedy filling routinge for printer path generation
- local optimization of tracks
- 'typewriter.py' can be run from command line
  with single argument giving the name of the
  file to print. Currently simulates.
Emacs mode line got removed?
Concurrent axes movement
For speed up and to allow to use maximum norm (was already in code)
for estimating print path time.