Ical import fix
In previous Orage versions, orage.ics was opened and closed for every single event import, it made imports of larger ical files very time consuming. This MR open ical file before first event import and closes after last import, this reduces drastically time for importing.
This MR have some minor improvements for reminder time calculations and removed some messages.
Closes #8 (closed). (Import probably failed by DBus timeout, DBus code part is now replaced with GtkApplication)
Edited by Erkki Moorits