Preparing debian packaging for 2.3 release.

git-svn-id: svn://svn.code.sf.net/p/dmtcp/code/trunk@2817 ba6dc0ae-232f-0410-883f-9ebac64fc565
Updated version number for fedora/opensuse spec files.

git-svn-id: svn://svn.code.sf.net/p/dmtcp/code/trunk@2818 ba6dc0ae-232f-0410-883f-9ebac64fc565
Added news for 2.3 release.

git-svn-id: svn://svn.code.sf.net/p/dmtcp/code/trunk@2819 ba6dc0ae-232f-0410-883f-9ebac64fc565