Bug with reset form

[JBriggs666]

I encountered a bug with resetting the form, even on the demo page, when the reset function is called, the form is reset to ng-pristine, but the tr-trustpass field remains ng-dirty.

Also if the ngModel is reset so that the password parameter is an empty string, the model does not update the tr-trustpass field.

I've fixed these and put in a pull request.