Support App Components

[escv]

Currently the /content Folder only supports displayable Content for the /templates

The Idea is here to also support an App Component that displays a (client based) WebApp.
There could be an appname.app (structured) file inside the content page tree that consists of initialization config (required Resource files) and params for a WebApp.

There will be a simple app Template (part of younic) that consist of a App Root

Container to render the app into it. Doing some webpack logic can initialize an App here. The app can make use of a REST backend directly hosted on younic itself (OSGi R7 Bundles can host JAX-RS service endpoints).

Maybe there will be a resource/ts next to resource/js to support typescript apps that are transpiled (upon detected changes) and servered by the younic dispatcher.

younic is well suited for WebApps because of the focus on serving static file resources as well as the posibility to host a service endpoint using JAX-RS.