`defmacro` is for clojure, not my scheme,

i am the master of this scheme, i am the defacto macro writer, i don't
need a defmacro hook nor does it make sense for me to have one.
quick define->lambda test
support let form via let->lambda
function signatures
code transforms don't need the environment
test for seq? not for list? b/c

of Cons versus List types
eval-let test