master branch: Check for root user earlier

[dldinternet]

I recommend checking root privileges before the 'su - ' dependencies

[liandros]

Thanks dldinternet . I am part of the team of contributors to zmbkpose project, however I do not have much knowledge of the master branch to make your contribution merge My main contribution has been to add the branch "rewrite_proposal_v2.0". If you think deserves to be tested, you are invited to do so.