More stable and reliable way to set 'noValidate'

[chrisyip]

Setting 'novalidate' by jQuery.attr will throw SCRIPT3: Member Not Found exception in IE 7.

Coz standard browsers are all support form.noValidate = Boolean, and it's just setting a property to an object, IE 7 will not throw any exceptions, so can use form.noValidate = true instead jQuery way.

Demo and comparison: http://jsbin.com/iyoyam/2