starting python3 port

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branch : python3
Fix tests with binary fields

--HG--
branch : python3
Fix some doctests on Py3

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branch : python3
Assert the put method widget behaves as expected on both py3 and py2

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branch : python3
Fix PUT method being encoded by UnicodeString as b'PUT' when on python3

--HG--
branch : python3
Add travis and coveralls support
merge from master
Add mongodb service to travis
Add mako and genshi dependencies
add sieve dependency for travis
Run mongodb tests only on Py2.X due to missing Ming on Py3
Avoid coverage reporting for dojo and tw1 tests
install TW2 from github
Install from develop branch tw2 for travis
Markupsafe on Python3.2 must be previous to 0.16
Fix remove_whitespace_nodes on Python3.3
This should correctly install mongodb dependencies on Python2.X on travis
looks like dash doesn't work in extras_require
oops, pypi badge was actually pointing to the crank one
Avoid reporting coverage on test suite itself