numerical comparison operators: add tests for complex
some implementations (i.e ecl / clasp) fail to signal a type error when complex is passed as the only argument to them. Add tests:
(> #c(1 1)) ;-> type error
(>= #c(1 1)) ;-> type error
(<= #c(1 1)) ;-> type error
(< #c(1 1)) ;-> type error
(min #c(1 1)) ;-> type error
(max #c(1 1)) ;-> type error