Quick actions for document list

- support for quick actions (folders/documents)
- reworked project structure for document list (simplified naming and
hierarchy)

refs #20, #50

ng2-components/ng2-alfresco-documentlist/src/models/content-action.model.ts

@@ -16,6 +16,7 @@
  */
 
 export class ContentActionModel {
+    icon: string;
     title: string;
     handler: ContentActionHandler;
 }