[Bug/Feature] Make behaviour of booking view more deterministic and configureable

[T3rminat0r]

Currently, the booking UI, by default, shows "today", "now" until "end of business-day" (from settings), when it's initially, opened, I believe. While that is reasonable, if I then change the enter time, the leave time does change, too (which makes no sense, if I just wanted to account for travel time to the office, for example...) Generally, I'd love to see a (global/org, and potentially a seperate per user) setting that decouples the end time from the start time, so it does not change, on it's own. Another "bug" behaviour happens, when I first edit the leave time, and then the start time, cause seatsurfing changes the leave-time again, after I edited the enter-time... instead of "knowing" that I just manually changed that...

Better UX would be to either a) change start time, based on leave-time changes, similarly to how it works with leave-time changing when enter-time is edited (that way, it would be consistent, and both would change, based on the respective other getting edited... need to make sure not to make this an endless loop, obviously...)

b) don't link the times together, at all, just let the user edit both times, in which ever order they deem best...

c) add a setting to switch between the current behaviour and the above option(s) chosen.... (both for the "default" for new users, and per user...)