Revert "MULE-6988:  The jetty transport does not have an option to configure the number of acceptor threads"

This reverts commit bf94c9266b0592c1001168b7a9b9720c6bad405a.
Revert "Merge pull request #28 from athieme/acceptors"

This reverts commit 0cfc6d3bdf1bc6689f6770402a2537c3abb4c456.