adding selecting by any attribute, not just name

Before:

   [name=Some Thing]

After:

   [name=Some Thing] or
   [label=Some Thing] or
   [value=Some Thing]

I need this so I can quickly match whatever text field happens to be the
one displaying 'First Name' on my signup form. So this now works:

  $("textfield[value=First Name]")
adding reference to searching by value to README