Fixing #737, for jQuery > 1.6: .attr() should be .prop() for properties

To retrieve and change DOM properties such as the checked, selected, or disabled state of form elements, use the .prop() method.

Signed-off-by: Mafl <fluer@vericom.at>
Merge pull request #777 from mafl/jQuery2

Fixing #737, for jQuery > 1.6: .attr() should be .prop() for properties