Fix lsbmajdistreleasee fact for Ubuntu

Since facter 2.2.0 'fixed' the lsbmajdistrelease fact for Ubuntu, we now have to regexp
for the value. The new value would be '10.04' whereas the old is '10'.

Signed-off-by: Ken Barber <ken@bob.sh>
Prepare a 4.0.0 release.
Further tweaks to changelog.
Improve port changing support.

This makes Debian 6 work, and hopefully Ubuntu 10.04 too.
Merge pull request #488 from apenney/fix-accept

Fix port changing.