Ensure we return a proper HTTP Multi-Status response code on PROPFIND.

Signed-off-by: Alex Zepeda <alex@inferiorhumanorgans.com>
Update quirks to support BlackBerryOS 10.2

This should close #9.

With BB10.1 the CardDAV client is completely broken. It ignores the
specification of a principal URL, ignores redirects from the root URL,
and it doesn't attempt to use RFC 5785 based autodiscovery.

With BB10.2 these bugs are all fixed and replaced by an improper
addressbook-multiget REPORT request. The depth is set to 1, where RFC
6352 is quite clear that this is improper. I'll add a quirk, but the
BB10 contacts library doesn't send a particularly useful user-agent.

Signed-off-by: Alex Zepeda <alex@inferiorhumanorgans.com>