merge: shortcircuit filemerge for identical files - use filectx.cmp to compare files - move merge messages into filemerge - kill the redundant resolving message - update tests

#!/bin/sh

hg init a
echo a > a/a
hg --cwd a ci -A -m a
hg clone a b
echo b > b/b
hg --cwd b ci -A -m b
chmod 100 a/.hg
hg --cwd b push ../a
chmod 700 a/.hg