Fix empty interface name when creating the first VNET jail.

Fixes #170.

usr/local/share/bastille/create.sh

@@ -147,14 +147,16 @@ generate_vnet_jail_conf() {
     local list_jails_num=$(bastille list jails | wc -l | awk '{print $1}')
     local num_range=$(expr "${list_jails_num}" + 1)
     jail_list=$(bastille list jail)
-    for _num in $(seq 0 "${num_range}"); do
-        if [ -n "${jail_list}" ]; then
+    if [ -n "${jail_list}" ]; then
+        for _num in $(seq 0 "${num_range}"); do
             if ! grep -q "e0b_bastille${_num}" "${bastille_jailsdir}"/*/jail.conf; then
                 uniq_epair="bastille${_num}"
                 break
             fi
-        fi
-    done
+        done
+    else
+        uniq_epair="bastille0"
+    fi
 
     ## generate config
     cat << EOF > "${bastille_jail_conf}"