Merge pull request #4 from skurfer/master

Contacts (Address Book) updates
64 bit changes

Conflicts:
	Info.plist
	QSObject_ContactHandling.m
Attempt to fix a crash reported by a user

Crash was inserting `nil` in `addObject`
In some cases, objectWithURL:... can return `nil` so it's worth checking to make sure the returned object isn't `nil`
Sort contacts alphabetically by surname
ignore empty notes
use the sharedAddressBook instance instead

This will hopefully prevent a crash we've seen.
rescan all contacts when a change is detected

…instead of trying to dig through all the changes.

This will hopefully prevent Quicksilver from locking up when multiple
notifications are sent. (Recent changes to Quicksilver prevent multiple
simultaneous scans of the same entry.)
remove an unused method

Quicksilver never calls this, but its presence might be confusing.
bump version to 2.1.1