UAA sample is needed for local development

[jkonicki]

Currently, our UAA sample on works on CF. It would be beneficial to have a sample for local development also.

[ccheetham]

The CI for CloudFoundrySingleSignon builds and publishes its own UAA app.

https://github.com/SteeltoeOSS/Samples/blob/2.x/Security/src/AspDotNetCore/CloudFoundrySingleSignon/CloudFoundrySingleSignon.feature#L13-L15

A local example could leverage this approach.

[TimHess]

added in #331