revparse_single: add support for non ascii paths (#207)
Release v0.18.0
Now Repository.head returns a reference (#203)

Now Repository.head behaves like libgit2's git_repository_head, it
returns the resolved reference. These two lines are equivalent:

  ref = repo.head
  ref = repo.lookup_reference('HEAD').resolve()

Before it returned a commit.
Merge branch 'master' into oid

Conflicts:
	test/test_repository.py