email: fix fallback sending to multiple admins If no recipients are set, emails are sent to all admins and the address specified in the config file setting 'email_to'. However, the existing code did not cater for the fact that multiple addresses could be set there: the setting was treated as a single string and passed along as-is. Adapt the code to split the email_to contents on a comma, as this is the separator expected by backlash.

# 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
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