Merge pull request #298 from fredericbonjour/Admin

Enhanced DocumentPickers and Menus management.
Merge pull request #299 from fredericbonjour/Admin

Added (experimental) Tasks list on the Dashboard :)
Add Http Rest 'admin/currentTasks' route
Fix Catalog, Price and Tag module setup
Fix event in Http.Web
Use 'admin/currentTasks/' in backoffice
Fixed getLabelKey() test on AbstractModelTest.
Add generic label property name
Merge pull request #300 from inthause/documents

Add Http Rest 'admin/currentTasks' action
Add new sample block Rbs_Catalog_Category
Merge pull request #301 from inthause/documents

Add new sample block Rbs_Catalog_Category
Add backoffice javascript REST.collectionTransformer() and  REST.resourceTransformer
Remove Rbs_Brand from Rbs_Catalog backoffice menu
Update \Rbs\Price\Documents\Tax::getRate
Merge pull request #302 from inthause/documents

Remove Rbs_Brand from Rbs_Catalog backoffice menu
Update \Rbs\Price\Services\PriceManager

Add Rbs_Commerce Twig Extension
Merge pull request #303 from inthause/documents

Update \Rbs\Price\Services\PriceManager
[NEW] Product Prices List
Merge pull request #304 from franckstauffer/master

[NEW] Product Prices List
Fixed loading of `<rbs-document-list/>` when no `model` attribute is set.