Full support for Python 2.6+ and 3.3+ with one common codebase (without 2to3)
Merge branch 'py3-2to3' into py3-common, so that 2to3 will be not used
Removed distribute_setup.py due to obsoletion.

"distribute" is obsoleted. The latest one is only a stub for use the new
"setuptools". The file "distribute_setup.py" also didn't work with any
Python 3 solution.