textbox test examples need <label> element

[Becky Gibson]

Since many people will use the test files of examples on how to use the widgets, the example files should be marked up for proper accessibility. The current examples in test_validate.js use just a span to indicate the label for the textboxes. Please update to use the <label for="inputId">Label text </label> to properly indicate the label. For example:

<div class="formQuestion">

<span class="emphasise"><label for="q1">First Name: </label></span> <span class="noticeMessage"> Textbox class, Attributes: {trim: true, ucFirst: true, class: 'medium'}, First letter of each word is upper case.</span>

</div>

<div class="formAnswer">

<input id="q1" type="text" name="firstname" value="testing testing" class="medium"" dojoType="Textbox" trim="true" ucfirst="true" />

</div>

[Douglas Hays]

(In [7296]) Fixes #2445