Clarify documentation regarding chaining and OO style

[russelldavis]

At http://documentcloud.github.com/underscore/#chaining, it says:

Using the object-oriented style allows you to chain together methods. Calling chain on a wrapped object will cause all future method calls to return wrapped objects as well.

Especially given the example above that in the documentation, it's easy to (mis)interpret that as meaning "_([1, 2, 3]).map(...) is equivalent to _.chain([1, 2, 3]).map(...) (which of course isn't true)

It might be clearer to leave out the "Using the object-oriented style" bit, since chaining can be done as both OO-style (_(x).chain()) and functional-style (_.chain(x))

Finally, it would be nice to clarify the "probably should" comment in the changelog for version 1.2.4:

You now can (and probably should) write _.chain(list) instead of _(list).chain().

Is that just a style issue, or is there something else to it? (See some confusion about the issue at http://stackoverflow.com/questions/9626512/what-is-the-preferred-way-of-chaining-underscore-js-functions)

Thanks!