add merge command. means same thing as "update -m".
repo.addchangegroup method now returns number of heads modified and added,
so command line can tell whether update or merge needed. this makes
tiny change to ssh wire protocol, but change is backwards compatible.
pull command now returns 0 if no changes to pull.
abort: Connection refused
255
copy: No such file or directory
changeset: 0:53e17d176ae6
tag: tip
user: test
date: Mon Jan 12 13:46:40 1970 +0000
summary: test
requesting all changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
1 files, 1 changesets, 1 total revisions
foo
pulling from old-http://localhost:20059/remote
searching for changes
no changes found