Another bug slipped through.
Removed the design document.
Fixed Issue #53.

The RecurrenceIterator is literally the hardest thing I've written so
far, and I hate how I implemented it.

I hope I can one day re-build it so it's a million times more elegant. I
wish upon no one to write an implementation for RRULE though.
Bumped version and set release date.
Merge branch '2.1'

Conflicts:
	ChangeLog
	lib/Sabre/VObject/Version.php
Minor fixes in unittests.