Fix a dangling doc reference, and add a doc check to tox and travis.

.travis.yml

@@ -35,3 +35,4 @@ script:
     - if [[ $TRAVIS_PYTHON_VERSION == 2* && $DEPS == true ]]; then python -m tornado.test.runtests --resolver=tornado.platform.twisted.TwistedResolver; fi
     - if [[ $TRAVIS_PYTHON_VERSION != pypy && $DEPS == true ]]; then python -m tornado.test.runtests --resolver=tornado.platform.caresresolver.CaresResolver; fi
     - if [[ $TRAVIS_PYTHON_VERSION == '3.3' ]]; then python -m tornado.test.runtests --ioloop_time_monotonic; fi
+    - if [[ $TRAVIS_PYTHON_VERSION == '2.7' && $DEPS == true ]]; then cd docs && sphinx-build -E -n -W -b html . $TMPDIR/sphinx-html; fi

tornado/web.py

@@ -2034,8 +2034,9 @@ class StaticFileHandler(RequestHandler):
         This method may be overridden in subclasses (but note that it
         is a class method rather than an instance method).  Subclasses
         are only required to implement the signature
-        ``make_static_url(cls, settings, path)``; other keyword arguments
-        may be passed through `static_url` but are not standard.
+        ``make_static_url(cls, settings, path)``; other keyword
+        arguments may be passed through `~RequestHandler.static_url`
+        but are not standard.
 
         ``settings`` is the `Application.settings` dictionary.  ``path``
         is the static path being requested.  The url returned should be

tox.ini

@@ -202,3 +202,10 @@ basepython = python3.2
 commands = python -O -m tornado.test.runtests {posargs:}
 deps =
      mock
+
+[testenv:py27-docs]
+basepython = python2.7
+changedir = docs
+deps = sphinx
+commands =
+    sphinx-build -q -E -n -W -b html . {envtmpdir}/html