Python3 compliant
Most noticeable changes are:
- Compatibility with Python3 (tested on Python 2.6, 2.7, 3.2 and 3.4)
- Support for Mar555 flat panel
- Optimization of CBF reader (about 2x faster)
- Include tests into installed module: fabio.tests()
- Tests data can be found in /usr/share/fabio/testimages or dynamically downloades into a temporary folder