to allow graceful connectionClosedOnError() disconnects, since we
received a bunch of reports where the counter seems wrong, which is
causing a NPE in a thread pool executor, causing the VM or Android App
to terminate.
Now we throw the StreamManagementCounterError instead.
from o.jsmack.tcp.sm, as XEP-198 Stream Management is not an "XMPP over
TCP" exclusive feature. It could also be use together with the Websocket
binding of XMPP, so we may have a smack-streammangement in the
future. This change prepares for that by moving the SM code out of the
XMPP TCP package namespace.
