Refactored some methods in calendar module:
- move methods into own file
- dont call shorten method from titelTransform because why? just call
them after each other.
- added tests for util methods
- cleaned up other tests
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Co-authored-by: veeck <michael@veeck.de>
When trying to debug why the tests broke for
https://github.com/MichMich/MagicMirror/pull/2946 I found that the tests
does not wait for the app to start and close. So if the startup isn't
blocking that would fail.
So I added a callback for `close()` too and converted them to promises
for the `startApplication()` and `stopApplication()` and updated all the
e2e tests to await both. Will try to refactor all these callbacks to
promises in a later PR.
