PrincipalResource: Zap unneeded method (#children).

Signed-off-by: Alex Zepeda <alex@inferiorhumanorgans.com>
Reveal which verbs are supported by which endpoints.

Signed-off-by: Alex Zepeda <alex@inferiorhumanorgans.com>
BaseController: Clean up exception handling.

Now we will allow exceptions to bubble up as needed and maintain debug
logging.

Signed-off-by: Alex Zepeda <alex@inferiorhumanorgans.com>
ContactResource: Add sanity check.

If a media type is requested it had better be vCard or vCard v3.0.

Signed-off-by: Alex Zepeda <alex@inferiorhumanorgans.com>
BaseResource Fix #properties to return the proper format.

Return an array of hashes in the format that
DAV4Rack::Resource#get_property is comfortable with.

Signed-off-by: Alex Zepeda <alex@inferiorhumanorgans.com>
Add a version info string to the default HTTP/CardDAV response headers.

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