do not install foreign distro/OS config files

• Do not install the following configuration files which are not used within the
  Debian package of fail2ban:
  /etc/fail2ban/paths-fedora.conf
  /etc/fail2ban/paths-freebsd.conf
  /etc/fail2ban/paths-osx.conf
  Closes: Debian bug #767123 (https://bugs.debian.org/767123).

Signed-off-by: Christoph Anton Mitterer <mail@christoph.anton.mitterer.name>