[patch][cla] Add method to reference single items in a NodeList

[guest]

I often find myself wanting to work with a single item in a NodeList? but without losing all the wonderful features of the NodeList?. For example, to connect to a click event for a single item, you have to do something like:

dojo.connect(dojo.query("...")[2], "onclick", ...);

I suggest adding a method, maybe named at, items, or get (a la jQuery) that would take a list of indices and return them as a new NodeList?. It's sort of like slice but not quite. Some examples...

Add a click handler to the first paragraph:

dojo.query("p").at(0).onclick(...);

Do something with the 3rd, 5th and 9th paragraph:

dojo.query("p").at(3,5,9).forEach(...);

[guest]

Patch to add "at" method --D. Schontzler

[dante]

(In [14594]) fixes #7063 - add an .at() method to NodeList? to select small subsets of NodeList?'s as a new NodeList? - cla on file for Schontzler, David ... thanks!