Sub uri deployment

[ianwdunlop]

Eli Lilly need to deploy the explorer using a sub uri and a proxy. This requires the sub uri to be used by both the Rails and Ember routes. Also requires the routes to be passed to the JS side without the host details but with full path. This can be achieved by setting the relative_url_root and assets.prefix in the Rails config then passing it to Ember vi a JS global. Also using url_for and the only_path param set to true to generate the routes without hostname in the main app html.

eg var tsvCreateUrl = '<%= url_for controller: "core_api_calls", action: "tab_separated_file", only_path: true -%>?';