Updating project-wide contribution guidelines + publishing on opentelemetry.io

[AnaMMedina21]

As End-User SIG we can help other SIGs be more friendly to new contributions

• Audit each SIG’s Getting Started guidelines – are they clear? Standardized? beginner friendly? do they have instructions on getting dev environment setup? and do they have running “First issue” tags

• EUSIG can promote these first issues more frequently

[danielgblanco]

This may be relevant here open-telemetry/community#2051 as there is already some work in progress. As there's a Contributor Experience SIG recently formed, maybe this is outside of the scope of the end-user SIG?

I still think it'd be good for this SIG to come up with ways to promote end-users becoming active contributors, but I think that should be a different issue.

[danielgblanco]

Ah, there's this one already which is closer to what I mentioned...

#35