uniform treatment of ISABELLE_HOME/contrib vs. ISABELLE_HOME/..;
uniform treatment of ISABELLE_HOME/contrib vs. ISABELLE_HOME/..;

MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle