#288 Improve show/hide of metadata

renamed directives to be more clear
- scMetaDataButton renders the button for showing and hiding of the metadata panel
- scMetaDataPanel renders the metadata panel which can be shown or hidden
- metaDataTree renders the complex tree structure of a details object
#288 Improve show/hide of metadata

streamlined DOM
#288 Improve show/hide of metadata

added first e2e test for show and hide metadata