Some examples for the Async module. (#12477)
Some examples for the Async module. (#12477)

* Initial set of examples for PR.

* PR feedback from @dsyme, 1

* Update async.fsi

Co-authored-by: Don Syme <b77950cdf1a232368f529545a433dad696edb2c3@users.noreply.github.com>
dsyme/fsharp,dsyme/fsharp,dsyme/fsharp,dsyme/fsharp,dsyme/fsharp,dsyme/fsharp,dsyme/fsharp