Add complete rewrite of function for deleting own
identities:
- The goal behind rewriting the function is that the old code just
deleted all trust values assigned to the deleted identity which
eventually could corrupt the trust graph of other own identities.
- The fix for this is to replace the deleted OwnIdentity with a non-own
Identity
- Notice that I started the rewrite by copypasting the
restoreOwnIdentity function as the new behavior of deleteOwnIdentity is
some kind of symmetric to restoreOwnIdentity: Replacing an own identity
with a non-own one and vice versa is symmetric.
- NOT tested yet!