exit: support custom VRF imports

Ten minutes to set up and ten hours to convince Ansible to not be
quite so retarded. The list2dict filter seems to be the (or another)
missing piece. Now let’s rewrite everything else using it. Or not.

filter_plugins/util.py

@@ -0,0 +1,14 @@
+#!/usr/bin/python
+
+class FilterModule(object):
+    '''Helper filters to make Ansible less unpleasant'''
+    def filters(self):
+        return {
+            'list2dict': self.list2dict,
+        }
+
+    def list2dict(self, items, key):
+        '''
+        Like items2dict but keep entire dictionaries as values.
+        '''
+        return {item[key]: item for item in items}