[safety] Small fixes 2

1. Rename:

Connect to System Models ---> Add Traces to AF3 Models

Show System Model Reference ---> Show Traces to AF3 Models

Disconnect from Library --> Instantiate Pattern

2. Delete requirementspatterns.ecore and all dependencies

3. "Ref Explanation" in Properties view: "n" is missing. Maybe rephrase to make it shorter

4. Enforce creation of justification for any newly created strategy