Fix double message when trying to skip a mandatory wizard during

[foosel]

Problem

• run setup wizard (or trigger some other mandatory wizard steps to show up)
• try to skip a mandatory steps by clicking "Next" without filling it in
• Result: You get a warning that the step is mandatory twice

Solution

Find the reason for that and fix it.

[max246]

I have investigated a little bit on this issue, apparently on plugin bootstrapWizard is binding the click event twice in someone to the button NEXT and PREVIOUS.

I am not familar with this plugin but seems like the method "onTabShow" and "onTabChange" is getting called twice as soon as you click the button.

[foosel]

Merged and ready for 1.9.0

[foosel]

1.9.0 has been released.