Return the readable port in $port.
Add a minor test for CLI situation.
Remove nonworking test that called method that does not exist.
closes issue #30
Return NULL for both Port and PortReadable if asked in CLI context.
Fix some coding style.
Revert major style changes in the rest of the file.
Merge pull request #36 from SvenRtbg/issue-30

Return the readable port in $port.