Proposal for improvement: "pinned repository" with longer description

[heidivanparys]

A small proposal for improvement:

• make the Standards Tracker a "pinned repository" (compare e.g. https://github.com/ISO-TC211 to https://github.com/INSPIRE-MIF).
• update the description of the Standards Tracker, so it is more descriptive (a condensed version of the README file), because that is what people see when they go to https://github.com/ISO-TC211

[ronaldtse]

@heidivanparys I've just done the first!

[PeterParslow]

I've done the second - it has to be very cut down, because it can't even contain any new line characters!

[heidivanparys]

Thanks!