[churn] Ignore merge csets Merge changesets attributed a large number of lines to people that didn't actually develop it, but simply merged the code. By ignoring merges, we get a more accurate picture of how much code everyone changed.

#!/bin/sh
hg init
echo This is file a1 > a
hg add a
hg commit -m "commit #0" -d "1000000 0"
ls
echo This is file b1 > b
hg add b
hg commit -m "commit #1" -d "1000000 0"
hg co 0
# B should disappear
ls