bug fix in asa_acl module for missing candidate config

This bug was introduced accidentally when refactoring to 2.2.  The instance
of the candidate config was deleted.  This adds the candidate config
instance back

fixes #2890

network/asa/asa_acl.py

@@ -128,8 +128,10 @@ responses:
   type: list
   sample: ['...', '...']
 """
+import ansible.module_utils.asa
+
 from ansible.module_utils.netcfg import NetworkConfig
-from ansible.module_utils.asa import NetworkModule
+from ansible.module_utils.network import NetworkModule
 
 
 def get_config(module):
@@ -179,16 +181,22 @@ def main():
     match = module.params['match']
     replace = module.params['replace']
 
+    candidate = NetworkConfig(indent=1)
+    candidate.add(lines)
+
     module.filter = check_input_acl(lines, module)
+
     if not module.params['force']:
+        contents = get_config(module)
+        config = NetworkConfig(indent=1, contents=contents)
         commands = candidate.difference(config)
         commands = dumps(commands, 'commands').split('\n')
-        commands = [str(c) for c in commands if c]
     else:
         commands = str(candidate).split('\n')
 
     if commands:
         if not module.check_mode:
+            commands = [str(c) for c in commands if c]
             response = module.config(commands)
             result['responses'] = response
         result['changed'] = True