git-handler: turn refs from None to {} so that empty git repos can convert
setup: bump dep on dulwich to 0.9.4
tests: dulwich is now smarter about sending fewer objects, update output
test-timezone.t: add missing (but needed) trailing whitespace
overlay: add kludge to make sure we only ever give hexshas to dulwich
git_handler: iterate over new refs in sorted order to stabilize test output

An earlier patch already fixes the test expectations (oops), so this
just makes sure the tests always pass.
gitignore: gate feature on dirstate having rootcache and ignore having readpats

--HG--
extra : amend_source : 3b2f5145693b18b4dbf899925dec658097ac874f
testedwith: add 2.8.1

--HG--
extra : rebase_source : 06a5ce423038b5ed0f84a1957f600ce324ab3951
testedwith: drop 2.3.1, which has at least one test failure

--HG--
extra : rebase_source : bd3b50a14c78659698b77ad4c6cc8ca00e383899
test-subrepos.t: hide output from newer hg versions about active bookmarks

--HG--
extra : rebase_source : c16c681139f90a6e0bd1b9b273065be003c71c78
setup: bump version
Added tag 0.5.0 for changeset ef41e87ea11a
Added signature for changeset 2f7bd8db709f