evolve: delete evolvestate after aborting interrupted `next --evolve` We didn't use to delete the evolvestate after aborting an interrupted `next --evolve`. This patch makes sure we do that. The test changes demonstrate the fix and we add a CHANGELOG entry about the fix.

tests: check that we delete evolvestate correctly after abort/stop This patch adds test to check whether we delete the evolvestate correctly after aborting or stopping an interrupted evolve which is caused because of `next --evolve`.

changelog: update with issue5927 fix

evolve: set the second parent if we get conflicts while evolving This patch makes sure we set the second parent correctly if we run into conflicts while evolving. Also, we need to make sure to reset to one parent before committing.

evolvecmd: import mercurial.node module as nodemod We use node as a variable name at few places and the conflicts with variable name are not good. Moreover this practice is followed in core mercurial also.

tests: demonstrate the interrupted evolve does not set p2 This patch adds a test to demonstrate issue5927 which is about evolving not setting p2 correctly in interruption.

cleanup: remove unused import

cleanup: remove old comment that lost all meaning

template: remove compatibility layer for `showobsolete` The keyword exist in core since 4.2

exthelper: drop compatibility layer for `command` We dropped support for 4.2.

topic: drop compat layer for `command` We dropped support for 4.2

legacy: drop compat layer for "command"

drophack: drop compat layer for "command"

compat: drop compatibility layer for updatecaches The `repo.updatecaches` method is support since Mercurial 4.2

branching: merge with stable

obshashrange: force saving of stablesort and firstmerge cache For some reason the check in repo is not working for stable sort. We also force firstmerge to be saved as test show it was missing.