Add get_each function (#88) * get_each function returns an array with the values or a $default value in the case it does not exist of each item in a $coll * Fixed the error analysing code in get_each.php, parameter #1 $key of function Lambdish\Phunctional\_get_values_from_key expects string, int|string given. * get_each function documentation * get_each function will return an empty array when no item contains the expected key.