Form widget should use "application/x-www-form-urlencoded" for default enctype

[guest]

The 1.0.2 version of the dijit.form.Form widget defaults enctype to "multipart/form-data". This means that the following won't work:

<form id="fooForm" dojoType="dijit.form.Form" action="/foo" method="post">

Instead, this must be used:

<form id="fooForm" dojoType="dijit.form.Form" action="/foo" method="post" enctype="application/x-www-form-urlencoded">

Not a huge deal, but the HTML 4.01 spec defines "application/x-www-form-urlencoded" as the default (http://www.w3.org/TR/html401/interact/forms.html#adef-enctype), so it was a surprise to see that the Form widget uses something different.

[doughays]

Dup of #5746. Fixed in [12261].