pep-8 fixes
Minopr fix: Use the correct default port number.
Improve the dump file format.
User feedback revealed a few flaws:
- the preamble was not visible, because the user used line folding and long P-python-headers polluted his screen
- a user recognised the MIME format as an email and tried to open the dump with a mail reader.
Now I moved the X-python-headers to the embedded message.