Merge pull request #242 from fredericbonjour/Admin

Additions and enhancements un Backoffice UI.
[NEW] Add document property type 'StorageUri'
Merge pull request #243 from inthause/documents

[NEW] Add document property type 'StorageUri'
Fixed Markdown parser to use Media's public URL.
Removed useless console.log().
Added possibility to define custom quick actions, via the use of the <quick-actions></quick-actions> tag, inside the <rbs-document-list/>.