- Change references to /e/n/r to /r/n when it's safe to do;
also remove ifupdown-clean script.

Partially solved with use of PGF/TikZ:
{
- The documentation in pdf generated by the .dia files does not show
up properly (it is bigger than the PDF itself)

- There is currently no way to build an ifudown-doc package. Since dia
cannot be used without a $DISPLAY the only alternatives are to
either build the dia stuff manually (for autobuilders) and build the
docs with the package or build all the docs manually and use a
a 'clean-everything-but-docs' target to clean the package when building.
}

- More documentation on how to configure ifupdown for different goals
is needed. A lot of content is already available in
the Debian Reference, but more detailed examples would be useful
(and should be included in a separate ifupdown-doc package)
See: http://www.debian.org/doc/manuals/reference/ch-gateway.en.html#s-net-high)