Add core copy detection algorithm
This adds findcopies, which detects merge-relevant copies between
files in a pair of manifests back to the merge ancestor.
While the merge code invokes the copy detection routine, it does not
yet use the result.
#!/bin/sh
mkdir test
cd test
echo foo>foo
hg init
hg addremove
hg commit -m 1
hg verify
hg serve -p 20059 -d --pid-file=hg.pid
cat hg.pid >> $DAEMON_PIDS
cd ..
http_proxy= hg clone --pull http://localhost:20059/ copy
cd copy
hg verify
hg co
cat foo
hg manifest
hg pull