Add required files from FreeBSD 13.0 base release, update config

conf/bastille.conf.ext

@@ -17,6 +17,8 @@ bastille_zfs_prefix="bastille"
 bastille_zfs_options="-o compress=lz4 -o atime=off"
 bastille_compress_xz_options="-0 -v"
 bastille_decompress_xz_options="-c -d -v"
+bastille_compress_gz_options="-1 -v"
+bastille_decompress_gz_options="-k -d -c -v"
 bastille_network_loopback=""
 bastille_network_shared=""
 bastille_network_gateway=""