New version of the email-fmt.py external script

[Grzegorz A. H. <gr...@te...>]

Hi.

The script as it is included now with setedit works only to
format small files: the pipe opening the fmt command buffers
those lines, and if there are many of them, the script never ends,
because format is bufferint it's output too. To avoid this, this
new version opens a temporary file and calls fmt on it, much safer,
works with any length.