Conj - undefined keys/values returned when passing objects and maps

[philbaker]

I've found that conj works as expected for arrays but I'm getting undefined keys/values when passing objects and sets (conj_BANG_ works as expected). Happy to make a PR to fix

conj({name: "George", coat: "Tabby"}, {age: 12})
// { name: 'George', coat: 'Tabby', undefined: undefined }

var conjMap = new Map();
conjMap.set("name", "George");
conjMap.set("coat", "Tabby");
conj(conjMap, {age: 12});

// Map(3) {
//   'name' => 'George',
//   'coat' => 'Tabby',
//   undefined => undefined
// }

[borkdude]

Sure, PR welcome :)