More robust check in dimshuffle pattern
Fix tests in FAST_COMPILE
Use integer division for python 3 in test
Run one part on python 3.3, add FAST_COMPILE

- fix install of pydot by using the right version of pyparsing on python 2
- pydot does not run on python 3 for the moment
- run tests on the installed files, not the source
Merge pull request #2322 from lamblin/travis_py3

Run part of travis on Python 3