evolve: add a `--abort` flag for `hg evolve` command This patch adds a new flag `--abort` to `hg evolve` command which will abort the interrupted evolve going on undoes the changes created by the evolve command till now. The changes are bookmark movements, creation of evolved commits, obsolete the old commits in favor of evolved commits. In case when user changed things while the interrupted evolve, like did some actions which created a new commit on top of evolved commits, or changed phase of evolved commits to public, the evolve fails to abort as we should not strip out the new commit formed by user neither we can strip the public changeset. The abort fails and tell user to use `hg evolve --stop` instead. Right now bookmark movement is broken, and will be fixed in upcoming patches. Tests are added for the new flag.

evolve: don't allow updating or commiting when there is interrupted evolve We should make things simple in the starting and restrict user from doing things which can lead to problems. This is same as the rebase behavior.

evolve: internationalize the entry of --list in hg evolve help

evolve: add evolvestate as an argument to _finalizerelocate() This will help us to store bookmark changes to evolvestate to revert them in case when `hg evolve --abort` is called.

evolve: add evolvestate as an argument to evolvecmd.relocate() This will help us in passing it to _finalizerelocate() and store the bookmark changes which happend.

tests: add test about handling phase-divergent merges We don't handle phase-divergent merges and we should. Upcoming patches will add the ability to handle them.

evolve: show a message when evolution leads to no changes to commit In case of orphan resolution, evolution may result in no changes to commit. This patch adds a use message in such cases. This is same as the rebase behavior.