Update jquery.validity.css

[markvantilburg]

jquery3fix

In the demo website another change is also needed:

Demos/index.htm
summary information:

<div class="validity-summary-container">
    Here's a summary of the validation failures:
    <ul></ul>
</div>

to:

<div class="validity-summary-container" style="display:none;">
    Here's a summary of the validation failures:
    <ul></ul>
</div>

[markvantilburg]

FIXES #76