More docblocks
This version works with VObject 3.0.
Bumped versions.
Now works with 2.1
Merge pull request #338 from fruux/1.7-vobject-3.0

Integrating vObject 2.1 into SD 1.7
Merge branch '1.7' into 1.8

Conflicts:
	lib/Sabre/CalDAV/Version.php
	lib/Sabre/CardDAV/Plugin.php
	lib/Sabre/CardDAV/Version.php
Fixed vObject 2.1 bugs.
Merge branch '1.8'

Conflicts:
	composer.json
	lib/Sabre/CalDAV/Version.php
	lib/Sabre/CardDAV/Version.php