obshashrange: fix computation of affected ranges The computation of impacted nodes and associated revs is fully reworked. In addition,we introduce multiple new tests covering cases that were previous wrongly handled.

obshashrange: add more validation output to tests We are about to update the logic and add more tests.

obshashrange: correctly detect changeset directly affected by prune Before this changesets, parent of standard obsmarkers were wrongly considered affected and pruned changeset were wrongly not considered affected.

obshashrange: do not search for affected ranges above the highest we have It is a fast way to know we don't have an affected range for an affected revision.

obshashrange: do not search for affected stable range cache is unavailable Before this changeset we where resetting in all cases, and then looking for affected ranges. In addition is the stable range were not available, the functions silently returned no ranges affected. Now, do one or the other depending of the availability of the stable range cache. In practice we always do a broad reset because the code detecting affected changeset is currently buggy.

stablerange: build closure a bit less inefficiently The new way make me a bit less sad than the old one.

discovery: make sure repository wrapping happens in the right order Otherwise we may end up in situation were cache are not warmed in the right order, crashing.

branching: merge with stable

changelog: add an entry about the next --evolve fix

changelog: update 8.1.0 release date