Add warnings to inform users about the implications of changing the clearance level

[TwistMeister]

We should inform the user a bit more on the implications about changing the clearance leven on an OOI. In terms of inheritance as well als in terms of automatic scans that will use this level from then on.

[underdarknl]

N.b. The work on Nibbles might give us the possibility to actually show the user the changes and their effects before they are performed by the user.
see: #4054