updates for correctness:  Top level of `where` clause may now either consist of EITHER a predicate OR a normalized constraint (this is both for performance and simplicity-- and because it doesn't make the code to iterate over the where clause any more complicated)
updates for correctness:  Top level of `where` clause may now either consist of EITHER a predicate OR a normalized constraint (this is both for performance and simplicity-- and because it doesn't make the code to iterate over the where clause any more complicated)

see https://gist.github.com/mikermcneil/8252ce4b7f15d9e2901003a3a7a800cf for an example
balderdashy/waterline,luislobo/waterline