Hide renamed operations from reuses

[Matthias Schoettle]

When reusing and renaming operations (especially in the case of Association where this is done automatically), it can be too much to see all those operations (they are callable anyhow in the message views).

Therefore, we decided to by default hide all renamed operations that are not public. Using an action in the menu, the operations can be made visible, for example to see them and to make them public. From there, they can also be hidden again.

[Matthias Schoettle]

In the future, we might also want to do this for getters/setters.

[Céline Bensoussan]

This is done through this commit 133e281 and updated somewhat by this one d2b4458.

For now, it only applies to operations mapped in the Association concern reuse but could easily be applied to any other operations.