Upgrade to coverage 3.7.1 and have it auto-build itself on first use.

third_party/coverage-3.6/doc/api.rst

-.. _api:
-
-============
-Coverage API
-============
-
-:history: 20090524T134300, brand new docs.
-:history: 20090613T164000, final touches for 3.0
-:history: 20100221T151500, docs for 3.3 (on the plane back from PyCon)
-:history: 20100725T211700, updated for 3.4.
-:history: 20121111T235800, added a bit of clarification.
-
-
-The API to coverage.py is very simple, contained in a single module called
-`coverage`.  Most of the interface is in a single class, also called
-`coverage`.  Methods on the coverage object correspond roughly to operations available
-in the command line interface. For example, a simple use would be::
-
-    import coverage
-
-    cov = coverage.coverage()
-    cov.start()
-
-    # .. call your code ..
-
-    cov.stop()
-    cov.save()
-
-    cov.html_report()
-
-
-The coverage module
--------------------
-
-.. module:: coverage
-
-.. autoclass:: coverage
-    :members:
-
-
-Starting coverage automatically
--------------------------------
-
-This function is used to start coverage measurement automatically when Python
-starts.  See :ref:`subprocess` for details.
-
-.. autofunction:: process_startup