test-commit-interactive-curses: remove unused import of parsers

churn: use the non-deprecated template option in the examples

strip: make tree stripping O(changes) instead of O(repo) The old tree stripping logic iterated over every tree revlog in the repo looking for commits that had revs to be stripped. That's very inefficient in large repos. Instead, let's look at what files are touched by the strip and only inspect those revlogs. I don't have actual perf numbers, since internally we don't use a true treemanifest, but simply iterating over hundreds of thousands of revlogs takes many, many seconds, so this should help tremendously when stripping only a few commits.

strip: move tree strip logic to it's own function This will allow external extensions to modify tree strip behavior more precisely.