Uploaded the plugin to DiapDealer' PlugIn thread,
here
It's in post #19
Edit:
It converts quotes/apostophe and the mdash,ndash,ellipsis, and preserves html comments
and does the words that begin with an apostrophe - from an apos_exceptions.txt file
If you don't want it to do any of the (m/n)dash or ellipsis entities, you can comment out the lines (add a # to beginning of the line) in the smarten.py file
30, 31, 32 (calculate extras for the entities)
42, (add pre tags to comments)
56, 57, 58 (convert the entities)
119 (remove the pre tags from comments)