Icons broke down with 2.0.2
Created by: peshi
refer to http://twitter.github.com/bootstrap/base-css.html#icons Email address input example.
<form>
<div class="control-group">
<label class="control-label" for="inputIcon">Email address</label>
<div class="controls">
<div class="input-prepend">
<span class="add-on"><i class="icon-envelope"></i></span>
<input class="span2" id="inputIcon" type="text">
</div>
</div>
</div>
</form>