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>
Merge pull request #477 from kbarber/maint/3.4.x/facter-lsb-fix

Fix lsbmajdistreleasee fact for Ubuntu