Audit put for non-object input

[Raynos]

I don't know what put(hashKey, rangeKey, 'string') or boolean or number or null does currently.

If we treat the value to be inserted as DynamoDB JSON then we should throw a programmer error if it cannot be converted because a scalar was passed in instead.

[heapwolf]

there needs to be a test for that. The expected behavior of put(hashKey, rangeKey, null) should be trying to put a value of { NULL: true } (or something like that). In theory, all javascript types should be re-cast to dynamodb types