tweak READMe and use the new travis badge now that we moved to pypy/manylinux

Author: antocuni

README.rst

@@ -1,33 +1,32 @@
-manylinux-pypy
-===============
-
-.. image:: https://travis-ci.org/antocuni/manylinux-pypy.svg?branch=master
-    :target: https://travis-ci.org/antocuni/manylinux-pypy
+manylinux for PyPy
+==================
+.. image:: https://travis-ci.org/pypy/manylinux.svg?branch=master
+    :target: https://travis-ci.org/pypy/manylinux
 
 Docker image for building PyPy manylinux_ wheels.
 
 This image extends the official manylinux image by installing PyPy. For now,
 the only supported platform is ``x86_64``.
 
-.. manylinux: https://github.com/pypa/manylinux
+.. _manylinux: https://github.com/pypa/manylinux
 
 At the moment of writing, this image provide the two following versions of
 PyPy:
 
-  - PyPy2.7 7.1.1
+- PyPy2.7 7.1.1
 
-  - PyPy3.6 7.1.1
+- PyPy3.6 7.1.1
 
 The various PyPy versions are installed inside ``/opt/pypy/``, and they are
 also symlinked to ``/opt/python``. Moreover, each installation of PyPy
 contains also a ``python`` symlink; all the following commands are equivalent
 and run the PyPy interpreter, you can use whatever fits best in your build
 system:
 
-  - ``/opt/pypy/pypy2.7-7.1.1/bin/pypy``
+- ``/opt/pypy/pypy2.7-7.1.1/bin/pypy``
 
-  - ``/opt/pypy/pypy2.7-7.1.1/bin/python``
+- ``/opt/pypy/pypy2.7-7.1.1/bin/python``
 
-  - ``/opt/python/pp271-pypy_41/bin/pypy``
+- ``/opt/python/pp271-pypy_41/bin/pypy``
 
-  - ``/opt/python/pp271-pypy_41/bin/python``
+- ``/opt/python/pp271-pypy_41/bin/python``