#18 pass through "cvs diff" -p, --show-c-function options

[Hans Ulrich Niedermann]

Add syncmail support to pass through -p
--show-c-function options to the "cvs diff" command.

Changes in more detail:
* trivially add -p / --show-c-function parameters to
syncmail
* pass through the parameter to the "cvs diff" command
* document changes in syncmail __doc__ and
doc/syncmail.sgml
* recompiled doc/syncmail.sgml to doc/syncmail.1

This does not look very complicated, so I rate the
probability this introduces bugs as low. A first test
at libexif CVS indicates it works as intended.

[Hans Ulrich Niedermann]

patch to add passthrough support for "cvs diff" -p, --show-c-function options