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

third_party/coverage-3.7.1/doc/install.rst

 .. _install:
 
 ============
 Installation
 ============
 
 :history: 20100725T225600, new for 3.4.
 :history: 20100820T151500, updated for 3.4b1.
 :history: 20100906T134800, updated for 3.4b2.
 :history: 20110604T213400, updated for 3.5b1.
 :history: 20110629T082400, updated for 3.5.
 :history: 20110923T081900, updated for 3.5.1.
 :history: 20120429T162500, updated for 3.5.2b1.
 :history: 20120503T234000, updated for 3.5.2.
 :history: 20120929T093600, updated for 3.5.3.
 :history: 20121117T095000, Now setuptools is a pre-req.
 :history: 20121128T203000, updated for 3.6b1.
 :history: 20121223T180800, updated for 3.6b2.
 :history: 20121229T112400, updated for 3.6b3.
 :history: 20130105T174400, updated for 3.6.
+:history: 20131005T210600, updated for 3.7.
+:history: 20131212T213500, updated for 3.7.1.
 
 
 .. highlight:: console
 .. _coverage_pypi: http://pypi.python.org/pypi/coverage
 .. _setuptools: http://pypi.python.org/pypi/setuptools
 .. _Distribute: http://packages.python.org/distribute/
 
 
 Installing coverage.py is done in the usual ways. You must have `setuptools`_
 or `Distribute`_ installed already, and then you:
@@ skipping 10 matching lines @@
 or even::
 
     $ easy_install coverage
 
 .. __: coverage_pypi_
 
 
 Installing from source
 ----------------------
 
-Coverage.py includes a C extension for speed. If you are installing from source,
-you may need to install the python-dev support files, for example with::
+Coverage.py includes a C extension for speed. If you are installing from
+source, you may need to install the python-dev support files, for example
+with::
 
     $ sudo apt-get install python-dev
 
 
 Installing on Windows
 ---------------------
 
 For Windows, kits are provided on the `PyPI page`__ for different versions of
-Python and different CPU architectures. These kits require that `setuptools`_ be
-installed as a pre-requisite, but otherwise are self-contained.  They have the
-C extension pre-compiled so there's no need to worry about compilers.
+Python and different CPU architectures. These kits require that `setuptools`_
+be installed as a pre-requisite, but otherwise are self-contained.  They have
+the C extension pre-compiled so there's no need to worry about compilers.
 
 .. __: coverage_pypi_
 
 
 Checking the installation
 -------------------------
 
-If all went well, you should be able to open a command prompt, and see
-coverage installed properly::
+If all went well, you should be able to open a command prompt, and see coverage
+installed properly::
 
     $ coverage --version
-    Coverage.py, version 3.6.  http://nedbatchelder.com/code/coverage
+    Coverage.py, version 3.7.1.  http://nedbatchelder.com/code/coverage
 
 You can also invoke coverage as a module::
 
     $ python -m coverage --version
-    Coverage.py, version 3.6.  http://nedbatchelder.com/code/coverage
+    Coverage.py, version 3.7.1.  http://nedbatchelder.com/code/coverage