Put new function in alphabetical order

Addresses review comment:
https://github.com/erikrose/more-itertools/pull/36#discussion_r10687235
Properly format arguments in docstring

Addresses review comment:
https://github.com/erikrose/more-itertools/pull/36#discussion_r10687277
Don't use capital variable name

Addresses review comment:
https://github.com/erikrose/more-itertools/pull/36#discussion_r10687292