shrink-revlog: add "reverse postorder" and "postorder reverse" toposorts.
Based on a patch by Benoit Boissinot, adapted to the pluggable sort
algorithm design. toposort_reversepostorder() is a very good
performer; it's designed to recreate what the revlog would have looked
like if Mercurial had parent deltas now. toposort_postorderreverse()
is unstable and very inconsistent, but perhaps with some work it could
be made better.
#!/bin/sh
hg init
echo This is file a1 > a
hg add a
hg commit -m "commit #0" -d "1000000 0"
touch b
hg add b
rm b
hg commit -A -m"comment #1" -d "1000000 0"