[This is preliminary documentation and is subject to change.]
Installs the given object as an associated member of this object. This object is flagged as modified. If there was a previous object set in this member, and if that object's class has the Log Associations function, then a link action is created which will remove the old link at the next commit. If the class of the new object has the Log Associations function, then a link action is created which will create a new link at the next commit. Remember these classes can be different subclasses of the declared class of the member, so perhaps only one of these actions will take place.