Add the causing exception to the XMPPExceptions thrown in XMPPConnection
Description
XMPPConnection.connectUsingConfiguration() doesn't include cause when throwing exceptions. Debugging connection problems would be significantly easier if the thrown exception chained to the exception that caused the failure.
XMPPConnection.connectUsingConfiguration() doesn't include cause when throwing exceptions. Debugging connection problems would be significantly easier if the thrown exception chained to the exception that caused the failure.
aSmack Issue #34