support for full object/array comparisons?

I think it might make sense to support comparing objects and/or arrays using the Equals/NotEquals operators. For objects, this would come in the form of comparison that the keys and values match (but not necessarily the ordering), and for arrays that the elements and ordering match. I think this might actually be possible to implement today using a compound operator which decomposes an array or object into a set of EQUALs checks (and maybe something to confirm the length of the object/array matching).

Start by locating the Equals and NotEquals operators and the compound-operator implementation mentioned in the issue. Define and test the intended semantics for object key/value matching, including order independence, and array element matching with order preserved; done means both comparison forms have clear behavior and coverage.

Written by the indexing model from the issue text.