Change format of dhcp_subnets to be a dict

Top level key is now subnet CIDR, rather than a list containing dicts,
where subnet is a sub-key, so better structured

- Update to pass more modern ansible-lint
- Fix galaxy info
- Format filter plugin w/black
- BSD fixes - paths, listening IP for tftpd server

Change-Id: I490331bc2998f2afbef135545500d1fa07b626ff
diff --git a/molecule/default/prepare.yml b/molecule/default/prepare.yml
index 68ec77e..e6b92bf 100644
--- a/molecule/default/prepare.yml
+++ b/molecule/default/prepare.yml
@@ -12,6 +12,12 @@
       apt:
         update_cache: true
 
+    - name: Install ps command for Debian init.d script to function
+      apt:
+        name:
+          - "procps"
+        state: "present"
+
     - name: Create a bridge to nowhere so dhcpd can start during testing
       when: "'bridge0' not in ansible_interfaces"
       command: