Transport Guarantee Handling for Servlets (AS Integration)

This pull request is dependent on the following pull request being merged first: -
  https://github.com/undertow-io/undertow/pull/32

This pull request updates the subsystem so provide a 'ConfidentialPortManager' during the deployment process that can dynamically discover which HTTPS port to use in the redirect when a transport-guarantee of CONFIDENTIAL is encountered.

Further work will be required within the subsystem but before we do that we need to be sure we understand the relationship between the core of undertow and multiple listeners.

I would expect something along the lines of each listener possible registering it's own root handler wrapping the shared handler - this listener specific handler will then be responsible for attaching something to the HttpExchange to identify the exact listener the request has been received over, this attachment will then be used when deciding the port.

One situation I would like us to try and avoid is the common situation where a http listener and a https listener are defined but then additional configuration is added to the http listener to identify the redirect port.  There is a case for that in a number of scenarios especially when fronted by a proxy but by default I would like to keep the port discovery dynamic.