fix(debian): avoid `python-ufw` installation (`py2`-only)

* Fix #19

ufw/osfamilymap.yaml

@@ -1,9 +1,7 @@
 # -*- coding: utf-8 -*-
 # vim: ft=yaml
 ---
-Debian:
-  packages:
-    - python-ufw
+Debian: {}
 RedHat: {}
 Suse:
   packages:

ufw/osfingermap.yaml

@@ -1,12 +1,41 @@
 # -*- coding: utf-8 -*-
 # vim: ft=yaml
 ---
-Debian-8: {}
+# os: Debian
+Debian-10: {}
 Debian-9: {}
-Ubuntu-16.04: {}
+Debian-8:
+  packages:
+    - python-ufw
+
+# os: Ubuntu
+Ubuntu-20.04: {}
 Ubuntu-18.04: {}
-Fedora-28: {}
-Fedora-29: {}
-CentOS-7: {}
+Ubuntu-16.04:
+  packages:
+    - python-ufw
+
+# os: Fedora
+Fedora-32: {}
+Fedora-31: {}
+
+# os: CentOS
+CentOS Linux-8: {}
+CentOS Linux-7: {}
 CentOS-6: {}
-openSUSE-4.23: {}
+
+# os: Amazon
+Amazon Linux-2: {}
+Amazon Linux AMI-2018: {}
+
+# os: SUSE
+Leap-15: {}
+
+# os: FreeBSD
+FreeBSD-12: {}
+
+# os: Windows
+Windows-8.1: {}
+
+# os: Gentoo
+Gentoo-2: {}