Package docs for lockset with an example.

[MattWhelan]

Test for the example code.

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This change is 

[MattWhelan]

It's worth noting that the dining philosophers test executes in-order, even when a delay is introduced in the dine function. So Alice and Carol aren't able to execute in parallel, despite not contending for resources.

[bobvawter]

This would be excellent as a testable example: https://go.dev/blog/examples

A local copy of pkg.go.dev can be launched with the following:

go install golang.org/x/pkgsite/cmd/pkgsite@latest
~/go/bin/pkgsite -http :6060