Milestone M28 - google calendar sync, redirection fix and more

Let's go through what we got done in Milestone M28 (Jan 13 - Jan 26).

Bug fixes

• We have made progress in improving Google Calendar sync. We're trying to make it better in the coming milestone.

• External redirection for paid meetings wasn't working properly, this has been fixed.

• When the timezone of the browser and the timezone the client chooses from the selector are different, it causes a bug that prevents the booking of a slot. We were able to fix it as soon as it was reported.