[db] updates test xml files to reduces unneeded edges
[db] reorganized unit tests and added tests for checking that snaps only
report bands they will really connect to
[db] updates snaps to only report bands they will touch
[db] made parser less verbose
[db] got rid of extra comments in topology
[db] renames test.py to run.py to avoid confusion with the unittests in
tests.py
[db] changed the name of topology_plot to asciiplot in run.py
[db] makes some progress on the asciidraw layout mechanism