Turn this check into a go module

[sni]

Hi,

are you interested in migrating this plugin into a reusable module, like ex.:
https://github.com/ConSol-Monitoring/check_nsc_web
It is an empty "main" package and the check itself is in a resuable golang module.
That way, this plugin could be easier reused elsewhere (specifically i am trying to put
it into https://github.com/ConSol-Monitoring/snclient)
If you think this is a good idea, i would prepare a pull request to do so.

Cheers