Fix the documentation of the Meeting.get_by_date method
Add the possibility to filter the meetings by their name, server side
Expose in the internal API the possibility to filter the meetings server-side
Update the calendar_list so that it filters the meetings server side

It is cleaner and should also be much faster to filter the meetings server
side instead of iterating through all the meetings retrieved.
Add the possibility to set the end date via the ?delta argument

This way we can list all the meeting over 2 weeks by just setting the
start date in the url and use ?delta=15
Have delta take precedence over the end date set via the URL parameters
Add the possibility to set the end date in the url when listing meetings
Ensure end = None if we cannot parse a date from it
If we cannot parse a date in the end parameter, then end is None

Thanks @puiterwijk
Merge pull request #129 from fedora-infra/filter_db

Filter db