For Ubuntu >= 13.04 install lib32stdc++6 package

Ubuntu >= 13.04 does not have libstdc++6:i386 packages in default repositories.

Also, I don't think if we should throw an error for all i686 architectures.
Merge pull request #1 from AndreyChernyh/ubuntu-libstdc-fix

For Ubuntu >= 13.04 install lib32stdc++6 package