Make irssi module directory configurable

The hardcoded path does not work on all distributions and I can't think
of a reliable way to autodetect it.

Signed-off-by: Martin Milata <mmilata@srck.net>
Signed-off-by: David Goulet <dgoulet@ev0ke.net>
Add additional files into dist tarball

Signed-off-by: Martin Milata <mmilata@srck.net>
Signed-off-by: David Goulet <dgoulet@ev0ke.net>
Add spec file for building RPMs

Signed-off-by: Martin Milata <mmilata@srck.net>
Signed-off-by: David Goulet <dgoulet@ev0ke.net>