fixed bug in thms_containing; changed error/warning messages; added thms_resolving_with
fixed bug in thms_containing; changed error/warning messages;
added thms_resolving_with

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