focus on first invalid element

[arajay]

This was first raised in #22 but was closed without being addressed.

it looks like the default functionality attempts to scroll the user to the closest .labelvalidationMessage; it does not add focus to the actual input.

if those labels are hidden or are styled using absolute positioning (to fake tooltips) then the browser can't jump to the label.

Please update to actually add focus to the closest or first input with .has-error.

[Jakobovski]

please create a pull request.