Changes to PYTHONPATH so it includes VERSION

- accept empty string from focus_get
- map coords() return value through getdouble and splitlist

- move compile() inside try-except
- add code so you can do "python pdb.py <script> <arg> ..." to debug <script>

(then f may be None).

- Better staggering of windows
- Windows have zoombox by default, and zooming works
- DrawControls->UpdateControls
- Better scrollbar show/hide

underscores.