Copy date/time in start/end editor from end/start field

[pdav]

I regularly copy events to new ones (using "duplicate"/"p" key) and edit the new event by editing date and time. Therefore, I often need to edit twice the date and the time for both "start" and "end" fields.

A useful feature in the date and time fields would be a keybinding (e.g. "pastedatetime", mapped to "ctrl p") to paste the symmetrical field:

• in the "end date", "p" would paste the "start date" value
• in the "start time", "p" would paste the "end time" value
• and so on.