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

The badge hosting at 'pypip.in' has been broken for a while
now, it was supposed to be fixed in the following PR(s):

- https://github.com/badges/pypipins/issues/39
- https://github.com/badges/pypipins/issues/38
- https://github.com/badges/pypipins/issues/37

That does not appear to have actually happened and/or is not
getting addressed, so switch to a more reliable badge hosting
site that provides the same badge information.

Change-Id: Ia1fd048e8f1810c4aaabc24bd01c7f0c18b79fd6

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