Identity management component for re-connecting entity and agent

[koenhindriks]

It would be useful to add a component to EIS that supports identity management. The idea is that an entity may appear, disappear and reappear again in an environment (e.g., think of a user of a website) and provided that the entity has a unique identity can be reconnected to "its own agent'' again. Assuming that the agent is terminated when an entity disappears, this means that it must be possible to make the state of the agent persistent and to retrieve it to relaunch an agent with that exact same state when the entity reappears. The first step is to enable a basic form of identity management that facilitates re-connecting entities and agents based on identity; a second step would perhaps be to think about security.