Release v0.16.1

Highlights:

- Tag.target now returns the OID, not the object
- New method "Repository.status_file(path)"
- New function "discover_repository(...)"
- Supporting tree-builders
- Improving pygit2 on Windows
- Various bugs fixed, including a couple of segfaults

Thanks to Amit Bakshi, Bryan O'Sullivan, Carlos Martín Nieto,
Han-Wen Nienhuys and Yonggang Luo.

setup.py

@@ -89,7 +89,7 @@ with open('README.rst') as readme:
 setup(name='pygit2',
       description='Python bindings for libgit2.',
       keywords='git',
-      version='0.16.0',
+      version='0.16.1',
       url='http://github.com/libgit2/pygit2',
       classifiers=classifiers,
       license='GPLv2',