Update README.rst
Clarify our stance towards PyPI and the status of YAPF in general. Anyone can push a "release" to PyPI, but we don't officially do this at this time.
diff --git a/README.rst b/README.rst
index 32bb7bc..166013e 100644
--- a/README.rst
+++ b/README.rst
@@ -38,6 +38,11 @@
YAPF supports Python 2.7 and 3.4+.
+We consider YAPF to be "alpha" quality, currently. Therefore, we don't yet
+support official releases to PyPI and the most stable and correct version is
+at the tip of the ``master`` branch in this repository. We plan to make a
+first beta release (including to PyPI) in the next few weeks.
+
If you intend to use YAPF as a command-line tool rather than as a library,
installation is not necessary. YAPF supports being run as a directory by the
Python interpreter. If you cloned/unzipped yapf into ``DIR``, it's possible to