Aliases

[eswdd]

We'd like to be able to "alias" a path so that a request for say "/webping" actually gets re-routed to "/customContext/health/v3/summary"

[eswdd]

Gist on how to configure this: https://gist.github.com/eswdd/8083033

[eswdd]

Fixed config aspect of impl and added some unit tests. Ideally need to add an integration test on baseline to ensure it doesn't get broken, but have tested manually.