Fixes for Reverse Proxy Go-Live (#6)

* Add new area for defining upstream systems.

* Example file for demonstration domain.

* Use the new upstream hosts section.

* Do the proxy directives in the main file.

* Commit any final changes.

* Fix example resource name.

* Mention the need to have ports specified in the upstream file, not server block.

* Adjust formatting.

Config/ReverseProxy/Dockerfile

@@ -18,3 +18,9 @@ RUN rm -rfv /etc/nginx/html
 # Add any static HTML websites.
 COPY ./config/html /etc/nginx/html
 RUN rm -rfv /etc/nginx/html/README*
+
+## Upstream Hosts ##
+RUN rm -rfv /etc/nginx/hosts
+COPY ./config/hosts /etc/nginx/hosts
+RUN rm -rfv /etc/nginx/hosts/README*
+