Include the sbin iptables wrappers (#224)

The previously merged PR#223 did not include the sbin wrapper
scripts in the docker image, and when iptables is detected under
the /sbin directory on the host it will fail with the following error:

  cp /usr/sbin/iptables-save.sbin.wrapper /usr/sbin/iptables-save
  cp: cannot stat '/usr/sbin/iptables-save.sbin.wrapper': No such file or directory

This commit fixes the issue.

package/Dockerfile.routeagent

@@ -18,7 +18,6 @@ RUN chmod +x /usr/local/bin/submariner-route-agent.sh
 COPY submariner-route-agent /usr/local/bin
 
 # Wrapper scripts to use iptables from the host when that's available
-COPY ./iptables.wrapper /usr/sbin/
-COPY ./iptables-save.wrapper /usr/sbin/
+COPY ./iptables*.wrapper /usr/sbin/
 
 ENTRYPOINT submariner-route-agent.sh