Revert "Ignore developer cruft."
Revert "Ignore developer cruft."

This reverts commit 2af839. OS-specific files should be added
to the developer's global gitignore.

dpnl87/supermarket,robbkidd/supermarket,nellshamrell/supermarket,juliandunn/supermarket,nellshamrell/supermarket,chef/supermarket,nellshamrell/supermarket,dpnl87/supermarket,leftathome/supermarket,nellshamrell/supermarket,leftathome/supermarket,chef/supermarket,tas50/supermarket,juliandunn/supermarket,leftathome/supermarket,dpnl87/supermarket,leftathome/supermarket,tas50/supermarket,robbkidd/supermarket,tas50/supermarket,robbkidd/supermarket,chef/supermarket,juliandunn/supermarket,robbkidd/supermarket,chef/supermarket,juliandunn/supermarket,dpnl87/supermarket,tas50/supermarket,chef/supermarket