- Update to v0.9.1
## Quick summary
* Tweaks to support the DAVMail server implementation
* v0.9.0 broke for python 3.5 and lower, due to usage of fstrings. v0.9.1 has been tested with python 3.5.
* Discovery of some cases of broken support of recurring events on the server side, and logging of errors (optionally raising of errors)
* New method .close on the DAVClient object.
## Minor changes
* Quite some users are complaining because recurring events aren't supported - which is intentional, because the server is supposed to take
care of that. Unfortunately quite some servers doesn't. Thanks to cos, at least we now have some code in place to log an error
(or optionally raising an error) when recurrences aren't taken care of (though, it only works if the server is returning non-expanded
recurring events - if searching for a recurrence and the server doesn't find it, then ... no error logged).
The error message is referring to https://github.com/python-caldav/caldav/issues/157
* New method `.close` on the DAVClient object
## Documentation fixes
* Added the fastmail caldav URL to the documentation - including note that they are picky on the trailing slash
- ref https://github.com/home-assistant/core/issues/66599
* Keeping the changelog up-to-date
## Bugfixes
* v0.9.0 broke on elder python versions due to an f"string". The f-format was introduced in python 3.6. Anything below is actually
End of Life versions, but still ... it's a very small effort here to preserve compatibility with elder python versions.
* The library had some difficulties with the DAVMail server - at one point it does not return a calendar home set property, and at
another point the calendar home set URL is the same as the calendar URL.
* The `URL.canonical()` method should rewrite variants of the same URL into something that will be equal - some work has been put making it more robust.
Issues: https://github.com/python-caldav/caldav/issues/189. f-strings discussed outside github.
## Linting
Removal of some extra white space
## Testing framework and incompatibility matrix
* The testTodoDatesearch is pesky - because every server has different visions on how (or weather) to support recurring tasks.
Added yet more complexity to allow the test code to pass on different servers.
* Removed some silly test code in testSetCalendarProperties - seems to be just recreating a calendar, which we do in the setup of any test