update ngModel dirty flag when color is changed

[ncourtial]

Hi,
When you change color in color-picker, model dirty flag isn't updated.
Maybe adding the following line in ngModel watch would correct the problem :
if($scope.isValid)
control[0].$setDirty()

Cheers,
Nathan

[ruhley]

Fixed in 6394a35 and released in v0.3.5.

Thanks for helping improve the library