A convenience method that grabs the raw input stream and decodes
the JSON into an array.

If $assoc == true, then all objects in the response will be converted
to associative arrays.

@param boolean $assoc   Whether to return objects as associative arrays
@param integer $depth   How many levels deep to decode
@param integer $options Bitmask of options

@see http://php.net/manual/en/function.json-decode.php

@return mixed