Add coverage

tools/telemetry/third_party/coverage/doc/api.rst

+.. Licensed under the Apache License: http://www.apache.org/licenses/LICENSE-2.0
+.. For details: https://bitbucket.org/ned/coveragepy/src/default/NOTICE.txt
+
+.. _api:
+
+===============
+Coverage.py 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.
+.. :history: 20140819T132600, change class name to Coverage
+
+
+The API to coverage.py is very simple, contained in a module called `coverage`.
+Most of the interface is in the :class:`coverage.Coverage` class.  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 :class:`coverage.CoverageData` class provides access to coverage data
+stored in coverage.py data files.
+
+.. toctree::
+    :maxdepth: 1
+
+    api_coverage
+    api_coveragedata
+    api_plugin