After many changes hash computed on databse could only be used to
check if  hfm can be updated to a given new version. The hash cannot be used
to check if the database schema for a given hfm version was modified,
becuase it does not take all haf elements for computation. It means
there is no need to have stored hash of the databas because it has no
usage, moreover it is misleading and could mask that the some parts of
 the schema was modified.

Warning: the change modifies hafd schema, what means that old hfm
versions cannot be updated to it.