Pressing 'Enter' key shall always save the event.
So focusing on 'Add' button after selecting calendar is redundant.
Instead, focus on the entry, so that the user can add more text without
manually focusing.
https://bugzilla.gnome.org/show_bug.cgi?id=778373
On week view, we want to create events that span 1 day, but with
different hours. The current code of Quick Add popover, however,
doesn't support that, as the only test case up to now was month
and year views - both not making use of timed events.
Fix that by adding the necessary comparisons, adapting the strings
and allowing events with the same date but different times.
If we add directly from the quick add popover, the event is
all day by default. If we're editing the event, it may or
may not be an all day event. In that case, if the user decides
to give it a time, we want it to be in the local timezone.
Instead of throwing it all for GcalWindow to handle,
add a new class called GcalQuickAddPopover that handles
event creation.
Events are always all day when created from the quick
add popover, unless the user wants to change it and click
'Edit Details' button.
In the future, we'll look forward adding natural language
support, so the user can type the times directly from the
entry (like e.g. "soccer at park from 10am to 11:30am").
