Add a disambiguation process

[Andrew Grimberg]

It is possible for some tools to provide events that are not unique across the event title. For example a guest books multiple stays within the sensor window and the tools provides the guest name which is then used as the event name. As such, the lock updating can get caught trying to update the same slot between the multiple events.

There are two possible methods to make this work:

1. Add unique information to the event names (start DD/MM ?) easy, but somewhat ugly
2. Store information in the sensor as to which slot was used. This does have added complexity related to an HA restart as any slots already assigned would have to be properly detected and stored