filenames conflict on case-insensitive filesystems
Trying to clone the bridgedb repository on macOS on a case-insensitive filesystem results in:
warning: the following paths have collided (e.g. case-sensitive paths on a case-insensitive filesystem) and only one from the same colliding group is in the working tree: 'bridgedb/Bridges.py' 'bridgedb/bridges.py' 'bridgedb/test/test_Bridges.py' 'bridgedb/test/test_bridges.py' 'doc/sphinx/source/bridgedb.Bridges.rst' 'doc/sphinx/source/bridgedb.bridges.rst'
We should rename stuff so the code is easier to work on in a case-insensitive filesystem.