CompEditor: Allow unset recurrence for uneditable recurrences
I have imported my calendar from thunderbird/lightning. Now I have an appointment in evolution and when I open it, evolution says "This appointment contains recurrences that Evolution cannot edit". The question is: what should the user do now? The check box for recurrences is gray what means that the recurrences cannot be removed. And cannot be edited. So the only choice left is to delete the whole calendar entry?