* Add RequestID to the RequestScope
* Expose RequestID to auth & request loggers
* Use the RequestID in templated HTML pages
* Allow customizing the RequestID header
* Document new Request ID support
* Add more cases to scope/requestID tests
* Split Get vs Generate RequestID funtionality
* Add {{.RequestID}} to the request logger tests
* Move RequestID management to RequestScope
* Use HTML escape instead of sanitization for Request ID rendering
* Use a specialized ResponseWriter in middleware
* Track User & Upstream in RequestScope
* Wrap responses in our custom ResponseWriter
* Add tests for logging middleware
* Inject upstream metadata into request scope
* Use custom ResponseWriter only in logging middleware
* Assume RequestScope is never nil
Reorganized the structure of the Request Utils due to their widespread use
resulting in circular imports issues (mostly because of middleware & logger).
