add babel to our extra tests

test/extra/babel_test.py

+import os, sys, subprocess
+from test_helper import create_virtenv, run_test
+
+ENV_NAME = "babel_test_env_" + os.path.basename(sys.executable)
+SRC_DIR = os.path.abspath(os.path.join(ENV_NAME, "src"))
+PYTHON_EXE = os.path.abspath(os.path.join(ENV_NAME, "bin", "python"))
+BABEL_DIR = os.path.abspath(os.path.join(ENV_NAME, "src", "babel"))
+NOSETESTS_EXE = os.path.abspath(os.path.join(ENV_NAME, "bin", "nosetests"))
+
+packages = ["nose==1.3.7", "pytz==2015.4", "-e", "git+http://github.com/mitsuhiko/babel.git@1.3#egg=Babel"]
+create_virtenv(ENV_NAME, packages, force_create = True)
+
+subprocess.check_call([PYTHON_EXE, "setup.py", "import_cldr"], cwd=BABEL_DIR)
+subprocess.check_call([PYTHON_EXE, "setup.py", "build"], cwd=BABEL_DIR)
+subprocess.check_call([PYTHON_EXE, "setup.py", "install"], cwd=BABEL_DIR)
+
+expected = [{"ran": 227, "failures": 3, "errors": 3}]
+run_test([NOSETESTS_EXE], cwd=BABEL_DIR, expected=expected)