Skip required options if version is parsed

If version was parsed the default behaviour is to print the version string,
but this is not done if there are required flags that have not been parsed.
This skips these required flags (so no IllegalArgumentException is thrown) if the version option is parsed.
Merge pull request #143 from torfredrik/flags_version_bug

Skip required options if version is parsed
Merge remote-tracking branch 'upstream/master' into HEAD
Updating version to 2.13.5