Initial remote Nextcloud integration support

setup/mods.available/conf/zpush/backend_carddav.php

@@ -0,0 +1,31 @@
+<?php
+/***********************************************
+* File      :   config.php
+* Project   :   Z-Push
+* Descr     :   CardDAV backend configuration file
+************************************************/
+
+
+define('CARDDAV_PROTOCOL', 'https'); /* http or https */
+define('CARDDAV_SERVER', '127.0.0.1');
+define('CARDDAV_PORT', '443');
+define('CARDDAV_PATH', 'NC_PREFIX/remote.php/dav/addressbooks/users/%u/');
+define('CARDDAV_DEFAULT_PATH', 'NC_PREFIX/remote.php/dav/addressbooks/users/%u/contacts/'); /* subdirectory of the main path */
+define('CARDDAV_GAL_PATH', ''); /* readonly, searchable, not syncd */
+define('CARDDAV_GAL_MIN_LENGTH', 5);
+define('CARDDAV_CONTACTS_FOLDER_NAME', '%u Addressbook');
+define('CARDDAV_SUPPORTS_SYNC', false);
+
+// If the CardDAV server supports the FN attribute for searches
+// DAViCal supports it, but SabreDav, Nextcloud and SOGo don't
+// Setting this to true will search by FN. If false will search by sn, givenName and email
+// It's safe to leave it as false
+define('CARDDAV_SUPPORTS_FN_SEARCH', false);
+
+
+// If your carddav server needs to use file extension to recover a vcard.
+//    Davical needs it
+//    SOGo official demo online needs it, but some SOGo installation don't need it, so test it
+define('CARDDAV_URL_VCARD_EXTENSION', '.vcf');
+
+?>