Corrected reference to assertMultiLineEqual method on unittest.TestCase.

The setUp method on FunctionalTest was adding a type equality function
for str. Instead of returning a reference to the TestCase.assertMultiLineEqual
method it was returning the string 'assertMultiLineEqual'. This caused
any test that used self.assertEqual(str, str) to throw an exception
as the string was not callable.
Merge pull request #10 from StuartMacKay/master

Fixed error in FunctionalTest.setUp which caused assertEqual to fail when comparing strs