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buteo-sync-plugin-carddav

This package provides a "client" synchronization plugin to the Buteo
sync framework.  It connects to CardDAV servers using a valid account
(accounts&sso framework) and synchronizes contact data from the
remote CardDAV service to the device and vice versa.

It is a two-way sync plugin.

Huge thanks to SabreDAV for the in-depth information available on their
site about CardDAV (http://sabre.io/dav/building-a-carddav-client/)