The command resets the topic to the default as configured in uhub.conf.
"clear" wrongly implies that the topic will be emptied.
Also added a plugin description in plugins.conf.
The mod_chat_history plugin provides chat history for all public chat messages.
Can be configured in the following ways:
- history_max: max number of messages stored in history
- history_default: the default number of messages to be returned when invoking !history
- history_connect: if > 0, then this number of messages is automatically sent when connecting to the hub
Removed the built-in !history command in favour of the mod_chat_history plug-in.
Make sure we unescape all chat messages before forwarding any of them to plugins.
Update example plugins.conf in documentation directory.
