graphlog: split the actual DAG grapher out into a separate method
This allows extensions like pbranch to use asciigraph() to graph dependencies
for patch branches, but could be used for basically any DAG.
echo % setting up repo
hg init test
cd test
echo a > a
echo b > b
hg ci -Ama
echo % change permissions for git diffs
chmod 755 a
hg ci -Amb
echo % set up hgweb
hg serve -n test -p $HGPORT -d --pid-file=hg.pid -A access.log -E errors.log
cat hg.pid >> $DAEMON_PIDS
echo % revision
"$TESTDIR/get-with-headers.py" localhost:$HGPORT '/rev/0'
echo % diff removed file
"$TESTDIR/get-with-headers.py" localhost:$HGPORT '/diff/tip/a'
echo % set up hgweb with git diffs
kill `cat hg.pid`
hg serve --config 'diff.git=1' -n test -p $HGPORT -d --pid-file=hg.pid -A access.log -E errors.log
cat hg.pid >> $DAEMON_PIDS
echo % revision
"$TESTDIR/get-with-headers.py" localhost:$HGPORT '/rev/0'
echo % diff removed file
"$TESTDIR/get-with-headers.py" localhost:$HGPORT '/diff/tip/a'
echo % errors
cat errors.log