I would like to suggest the addition to the standard library of a package to generate and parse UUID identifiers, specifically versions 3, 4 and 5.
The main reason I see to include it is that the most popular 3rd-party package (github.com/google/uuid) is a staple import in every server/db based Go program, as confirmed by a quick Github code search.
Additionally:
Addendum
Would like to point out how Go is rather the exception than the norm with regards to including UUID support in its standard library.
