prepare release 5.0.2

test: adapt to core change in graft and rebase The ouput changed we have to adapt

merge with stable

doc: drop rebase extension activation The dependency have been dropped.

evolve: remove the dependency to the rebase extension We do not use any rebase internal anymore.

evolve: remove the use of `rebase.concludenode` Half of this function is now done in `merge.graft` and the over part is easy to redo manually. So we remove the usage of this function to remove the dependency of evolve on the rebase extension.

evolve: use `merge.graft` instead of `rebasenode` The core mechanism is properly factorised and have a more stable API. This is also a good step toward removing the dependency between evolve and the rebase extension. This also avoid a breakage with the future 3.3 where some of the rebase API changed.