add a new AutoReceiptMode enum that specifies how delivery receipt
requests are handled. Default is to send receipts if the requstor is
subscribed to the user's presence.
Also make sure that messages contain an id if a receipt request is
added to it.
on package layer instead of Declarative Service (DS) approach.
Restructuring and cleanup of initialization process to ensure that all
internal config files are found by the corresponding bundle
classloaders.
SMACK-343
