In-progress cherry-picking detection + stop cherry-picking from current branch

If a cherry-pick failed then it actually awaits for you to continue or abort, but we don't seem to be detecting this. The next time the user attempts to do a cherry-pick they can't continue without going to the terminal.

Also, Git allows cherry-picking from the current branch, you should use reset for a specific revision instead for that. If you do specify a revision of a commit on your current branch it just fails and thinks it's still in progress. There must be a reason for this, but IMO it should return an error and abort the cherry-pick. Instead, the user has to manually abort from the terminal.

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error: a cherry-pick or revert is already in progress
hint: try "git cherry-pick (--continue | --quit | --abort)"
fatal: cherry-pick failed