email: add X-Kallithea-Notification-Type header To simplify email filtering, add a header indicating the type of email being sent. The 'type_' value corresponds to one of the types defined in class Notification in kallithea/model/db.py, e.g. 'cs_comment', 'pull_request', 'pull_request_comment', ...

# 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
.