Fixing up tests for Python 3.2

Changing from u"" syntax to using from __future__ import unicode_literals

This appears to resolve the test suite issues for 3.2 and the tests now pass ok

  (pymysql)kev@officedev:~/git/PyMySQL$ python3.2 ./runtests.py
  ................Set max_allowed_packet to bigger than 17MB
  ...........................s...x......s.........................................................x.......
  ----------------------------------------------------------------------
  Ran 120 tests in 4.152s

  OK (skipped=2, expected failures=2)
  No garbages!

Versions are as follows

  (pymysql)kev@officedev:~/git/PyMySQL$ mysql --version
  mysql  Ver 14.14 Distrib 5.5.35, for debian-linux-gnu (x86_64) using readline 6.2
  (pymysql)kev@officedev:~/git/PyMySQL$ python --version
  Python 3.2.3