templates: fix dropdown functionality of current menu item After 3e46e6b6a27a, the 'current' menu would have two class attributes and it would not work as a dropdown. For example, it was not possible to navigate from Admin>Users to Admin>User Groups. Instead, get rid of the is_current "helper" and just handle classes explicitly. That might be slightly more verbose but is also more explicit ... and it works.

# requirements.txt file for use as "pip install -r requirements.txt" as a
# readthedocs compatible alternative to "pip install -e ." which is a working
# alternative to "setup.py develop" which doesn't work with Mercurial 3.7
.