Remove always-true policy from UI

[SebastianOpriel]

As a user I do not want to have a destinct always-true policy. It is sufficient for a user to select "no policy" on a data offering. The UI or backend can manage to create such a always-true policy by itself. This would help UX.

Idea:

• On the page "contract definition", implement the "publish unrestricted" functionality.
• Hide the always true policy on "policies" page

[tmberthold]

Maybe also consider simply removing the "delete" button:

[SebastianOpriel]

At the Create Offer Wizard, we already deal with this hidden policy. Can we simply filter for the policy and remove it from the view?