Switch badges from 'pypip.in' to 'shields.io'

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now, it was supposed to be fixed in the following PR(s):

- badges/pypipins#39
- badges/pypipins#38
- badges/pypipins#37

That does not appear to have actually happened and/or is not
getting addressed, so switch to a more reliable badge hosting
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Change-Id: I93c43d6f09bc5240ce21206ddaf61b30227a88f4

README.rst

@@ -2,11 +2,11 @@
 stevedore -- Manage dynamic plugins for Python applications
 ===========================================================
 
-.. image:: https://pypip.in/version/stevedore/badge.svg
+.. image:: https://img.shields.io/pypi/v/stevedore.svg
     :target: https://pypi.python.org/pypi/stevedore/
     :alt: Latest Version
 
-.. image:: https://pypip.in/download/stevedore/badge.svg?period=month
+.. image:: https://img.shields.io/pypi/dm/stevedore.svg
     :target: https://pypi.python.org/pypi/stevedore/
     :alt: Downloads