Update Issue 28
(git-repo)

http://java.net/jira/browse/JSIP-444

Fix + non regression test on master
(cherry picked from commit 3a324bf5d9fd68628b0750fff1742c249c7d8ec0)

git-svn-id: https://svn.java.net/svn/jsip~svn/trunk@2270 8e71dc83-d81e-6649-80f2-80b843a9b2be
Bug 622: No media due to JSIP sending repeated ACK

The ACKs were dropped because CSeq numbers got out of order.  Fix is to prevent this from happening by preventing CSeq numbers from ever decreasing