Hi.
Here's the updated patch. It fixes a couple of small problems, and
includes documentation and tests (which I placed in a new file in
src/test/modules/test_extensions, on Petr's advice).
I wanted to post this before I went on to attempt any more grammar
cleanups. Please let me know if there's anything else you'd like to
see here.
Thanks again for your review and suggestions.
-- Abhijit