values.each and keys.each methods are depreciated, so they have replaced by
each_value and each_key respectively. This has done manually.
Closes https://github.com/openSUSE/osem/issues/1825
Also, the part of the schedule event is deleted and the length of the event types
changes to the nearest suitable after changing the length of the interval.
This closes#1220
Added an application helper method `time_with_timezone` to return time with the conference timezone which solves the issue of wrong timezone in `scheule.xml` and `admin/events#show`.
Fixes#1188
- Drop selected_event_schedule function
- Rename scheduled_room and scheduled_start_time to room and time as if there is no selected_schedule, the event is not scheduled.