hash(alg/tool/data_handle) are non-deterministic since
Algorithm, Tool and DataHandle use hash to construct
their "identity" (which is returned by their __hash__).
This makes the iteration order of sets of objects
non-deterministic, which can be a problem since, at least currently,
the names of Algorithms depends on instantiation order.
This is fixed here by using deterministic hashing.
Goes with Rec!3099 (merged)
See Moore!1737 (comment 5951216)
/cc @gunther