- Add extension points when receiving/sending a message
- Add extension point for setting the lock image
- Add extension point after clicking the send button
- Add extension point when typing
- Add a new menu button to choose the desired encryption
- Extend the PluginManager to hold a list of encryption plugins
ChatControlBase was split from ChatControl into its own module in commit
80221afc2c. With this split the import of the CommandContainer modules
was removed as well, likely because their members are not referenced
anywhere. However, importing these modules even when they are not used
directly is crucial because the contained CommandContainers are only
registered with the command system when their definitions are evaluated.
Import the modules with CommandContainers in chat_control_base.py to fix
the command system. Also add a comment stating more clearly why the
imports need to be kept around.