Fix CardDAV collections for OS X

Restored the previous behavior: only the personal addressbook is
returned and only the first source directory is returned (now sorted by
id so you can control which of your addressbook sources you want to
return).

SoObjects/Contacts/SOGoUserFolder+Contacts.m

@@ -61,7 +61,7 @@
 
 - (NSArray *) davDirectoryGateway
 {
-  NSArray *tag, *sources;
+  NSArray *tag, *sources, *sorted_sources;
   SOGoContactFolders *parent;
   SOGoUserManager *um;
   NSString *domain, *url;
@@ -71,9 +71,11 @@
   sources = [um addressBookSourceIDsInDomain: domain];
   if ([sources count] > 0)
     {
+      // Only return the first ID from the sorted list of sources
       parent = [self privateContacts: @"Contacts" inContext: context];
+      sorted_sources = [sources sortedArrayUsingSelector: @selector (localizedCaseInsensitiveCompare:)];
       url = [NSString stringWithFormat: @"%@%@/", [parent davURLAsString],
-                      [sources objectAtIndex: 0]];
+                      [sorted_sources objectAtIndex: 0]];
       tag = [NSArray arrayWithObject:
                        [NSArray arrayWithObjects: @"href", @"DAV:", @"D",
                                 url, nil]];