Reordering of tasks should be possible #7
Description
In the task list, a reordering of tasks should be possible.
They should displayed grouped by:
- today
- tomorrow
- upcoming (grouping all tasks the next two weeks)
- somedate (here are all without date)
When dropping into "tomorrow", the task gets tomorrow's date (similar for today). When dropping into "somedate", the date is unset. Dropping into "upcoming" the task receives the latest date in that range. If dropped after, it gets the date of that task. If it is dropped as first task, it gets the date of the before-first-task.