Exit 0 with no matched hosts

And also print to stdout not err

This lines up with how ansible-playbook will exit. 0 in the case of no
matched hosts. This makes it easier to script ansible commands w/
variable iventory input which may or may not have an entry for the
specific ansible task being scripted. No matched hosts is acceptable,
but matched hosts w/ failures is not.
Merge pull request #4817 from j2sol/zero-exit

Exit 0 with no matched hosts