data should accept a hash

[scott.gonzalez]

data should support

$(el).data({
    key1: val1,
    key2: val2
});

as an equivalent of:

$(el).data('key1', 'val1').data('key2', 'val2');

[Morgan]

add data from hash

[Morgan]

The patch check if key is an object, if so it sets data for each key/val pair.