Starting on config file based around HostGroups

ssh_config_utils/config_file.py

@@ -85,3 +85,9 @@ class ConfigFile:
                 file.write(text)
         else:
             text = fp.write(text)
+
+
+class GroupedConfigFile(ConfigFile):
+    def __init__(self, global_host, hosts):
+        self.global_host = global_host
+        self.root_group = HostGroup("")