Observe changes in definitions

The definitions shown in the definitions view are only reloaded when either switching subapps or changing the filters. It should be easy, clear, and one click away to reload the contents. (Note, a browser refresh also does not show the latest definitions state.). The configured view should stay the same when the contents are updated so that a developer does not loose their place - ie same filters and same scroll-location.

Example:

• Have any kind of defintion in a Yaml, for example an App
• Change anything in the defintion
• See its read and processed in the log.
• Close and open app to see the changes
• BUT: In the definitions app the old values are still displayed / is not updates to the latest state if the yaml's content

This is pretty bad for a developer, as he can never see in the definitions app the changes he did, can not be sure if the system really uses the values as the app displays it -> after any yaml change one needs to close the definitions app to be sure.

Dev notes:

• Implement auto-observation (like observation in resources or plain JCR apps)