First batch of UI changes

Registered by David Klasinc

- Add "main" and "options" tabs in the main UI
- Remove the stuff from in between the separators (except "Record Region") and put them in the "options" window
- Move "Record Region" to the bottom
- Rename "Countdown dialog" to "Countdown Splash"
- Remove the video toggle switch (useless)
- More
- Remove the audio toggle switches
- Remove the close button

Blueprint information

Status:
Not started
Approver:
David Klasinc
Priority:
Medium
Drafter:
David Klasinc
Direction:
Approved
Assignee:
George Karavasilev
Definition:
Approved
Series goal:
Accepted for unstable
Implementation:
Unknown
Milestone target:
milestone icon 1.3.2

Whiteboard

All done, just a few trivial fixes left :)

(?)

Work Items

Work items:
Combobox code refactoring: DONE
Audio source selection support: DONE
Move "Record Region" to the bottom: DONE
Rename "Countdown dialog" to "Countdown Splash": DONE
Remove the audio toggle switches and implement the "OFF" in the Audio Comboboxes)*: DONE
Remove the video toggle switch (useless)*: DONE
Improve the "Record Region" rectangle (in addition): DONE

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