**Acceptance criteria**

* The "+ Insert" of the ckEditor menu gets two new options: "Project attribute", "Work package attribute"

* Clicking that, opens a dialog where the user can select which attribute to show

* It is a single select

* _Open: How should this dialog look like?_

* After selecting an attribute from the dialog, the macro syntax (e.g. `projectValue:id:version`) gets rendered in the current cursor position within the ckEditor

* In v1, always the current workPackage and project are used.

* Begin of the insertion_Open:End of the insertion Begin of the deletion Open:End of the deletion When I am in a WorkPackage from another project: which project to Begin of the insertionuse?_End of the insertion Begin of the deletion use?End of the deletion