Date completions are triggered when entering 'due:' or 't:' (depends on
your configuration which tags you use).

Conflicts:
	setup.py
	topydo/Commands.py

Remove priorities from multiple todo items at once

+ Test new multi-todo functionality.
+ Change name of tests from set_prio to depri

Yes, I'm too tired for this. :/

Guess I'm too tired for this.

Add tests for EditCommand

Edit the archive file with '-d' option.

Split the CLI class into a CLI base class.

This implements archive option from #2.

Implementation of editing todos in $EDITOR

implements #2

- `topydo edit` will still open todofile in $EDITOR
- `topydo edit 1 2 3` will open tmpfile with corresponding todos
- `topydo edit -e @Home due:today` will open tmpfile with todos matching
   the expression