* New sequence objects (TODO: Make a good and efficient generalization)

* Global precomputed distance cache implemented as an precomputed distances filter (for fast substitution in existing implementations)
* Incompatiblity: PrecomputedDistancesFilterFactory requires a local abstract object as an argument to allow also automatic filter registration.
* LocalAbstractObject.getDistanceFilter registers the new filter and overrides any existing one (it did not overwrite it before)
* JavaDoc fixes