Typos and rewording
Moved email templates to a dedicated folder
Removed some debug statements
More semantic expressions
Small fixes and code cleanup

* Renamed some methods and files
* Replaced to lowercase true/false/none in jinja templates
* Prevented some unnecesary queries
* Small rewording in templates
* Addapted missing template to jinja
* Fixed broken link to videoconference survey
Moved RB blockings email to jinja