This puts manpages into "$out/lib/erlang/man" and also symlinks them
into "$out/share/man" with an "erl" suffix (similar to how Debian is
handling this) so those manpages are unlikely to collide with any other
manpages, like for example inet(3).
Closes#3396.
Signed-off-by: aszlig <aszlig@redmoonstudios.org>
Acked-by: Moritz Ulrich <moritz@tarn-vedra.de>