Feature/python3

Made a branch that makes it possible to use yampy on Python3. The fix is also backward compatible with Python2, so no need to two different branches. All tests work for both versions except for one test (see below) that fails with Python 3 in the werkzeug module which most likely does not support Python3.  

(python3)➜  yam-python git:(feature/python3) ✗ nosetests tests
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   ERROR: Failure: SyntaxError (invalid syntax (exceptions.py, line 111))
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Traceback (most recent call last):
  File "/home/dbrattli/.virtualenvs/python3/lib/python3.2/site-packages/nose/failure.py", line 38, in runTest
    raise self.exc_val.with_traceback(self.tb)
  File "/home/dbrattli/.virtualenvs/python3/lib/python3.2/site-packages/nose/loader.py", line 413, in loadTestsFromName
    addr.filename, addr.module)
  File "/home/dbrattli/.virtualenvs/python3/lib/python3.2/site-packages/nose/importer.py", line 47, in importFromPath
    return self.importFromDir(dir_path, fqname)
  File "/home/dbrattli/.virtualenvs/python3/lib/python3.2/site-packages/nose/importer.py", line 94, in importFromDir
    mod = load_module(part_fqname, fh, filename, desc)
  File "/cygdrive/c/Users/dbrattli/Documents/GitHub/yam-python/tests/integration_test.py", line 22, in <module>
    from .support.integration import TestCaseWithFakeYammerServer
  File "/cygdrive/c/Users/dbrattli/Documents/GitHub/yam-python/tests/support/integration.py", line 29, in <module>
    import flask
  File "/home/dbrattli/.virtualenvs/python3/lib/python3.2/site-packages/flask/__init__.py", line 17, in <module>
    from werkzeug.exceptions import abort
  File "/home/dbrattli/.virtualenvs/python3/lib/python3.2/site-packages/werkzeug/__init__.py", line 154, in <module>
    __import__('werkzeug.exceptions')
  File "/home/dbrattli/.virtualenvs/python3/lib/python3.2/site-packages/werkzeug/exceptions.py", line 111
    return u'<p>%s</p>' % escape(self.description)
                      ^
SyntaxError: invalid syntax

----------------------------------------------------------------------
Ran 142 tests in 0.077s

FAILED (errors=1)