This is an abstract superclass for singletons like ServerQuit, which provides a place for registering functions and objects for events that should happen when something happens in the server. No direct call to AbstractServerAction is required.
Subclasses return specific function selectors for objects that implement this as interface. Selectors are:
not for registry with a server, but analogous are:
Add an action or object for registry.
Can either be a Function to be evaluated (as first arg the server is passed in), or an Object that implements the message returned by -functionSelector. One object is only registered once, so that multiple additions don't cause multiple calls.
Server for which to register. If the symbol \default is passed in, the action is called for the current default server. If the symbol \all is passed in, the action is called for all current servers. If server is nil, it is added to \all.
Remove an item or object from registry. If server is nil, remove from all key.
Remove all items that are registered for a given server.