Ability to right align form icons.

This commit adds the ability to add right aligned form icons.

Example:
````
<div class="uk-form-icon">
	<i class="uk-icon-star"></i>
	<i class="uk-align-icon-right uk-icon-info" data-uk-tooltip="{pos:'right'}" title="Two-factor authentication code"></i>
	<input class="uk-width-1-1" type="text" name="secretkey" tabindex="0" placeholder="Security code" />
</div>
````
This example will show both a left and right aligned form icon.