edit dialog: reworked ui, implemented composite widget
Merge branch 'week-view' into backend-improvements

Conflicts:
	data/ui/edit-dialog.ui
manager: added 'sync-start' and 'sync-end' signals

When the event is added into an online account, EDS syncs it. It is really important to provide this information feedback to the user
new event widget: inactivate read-only calendars
date entry: fix wrong month selection on calendar popover
event-widget: implemented text position drawing

On Day and Week views, events should have their summary placed on center. This commit implements text positioning.
day view: draw event name on it's center
update header
update header
Merge branch 'backend-improvements' into week-view
Merge branch 'event-widget' into week-view
window: fix wrong geometry id saving

When the save_geometry method is called, save_geometry_timeout_id is not updated and points to an invalid ID. This commit fix it