[sync] Registry functions

[Anthony Mills]

Here are the registry functions I need for SyncML.
     listByActionUIDs($action) //returns an array of $shareids
     listUIDs() //returns an array of $shareids
     import($shareid, $data, $contenttype) //shareid can be blank, a new 
one is created and returned, the shareid is returned false otherwise
     export($shareid, $contenttype) //the object of contenttype is 
returned false otherwise
     remove($shareid) //true or false is returned

Thanks,

Anthony