Re-enable testsuite for numpy
WIP - fix dangling ref
Fix result type extraction

One has to remove the const qualifier of the return type to match the
specialization of ``pythran_to_python``
Fix bad implementation of str.strip

Empty string was badly handled
Fix rangeextract test case

There is no pythran converter for generators, so expand the generator to
return list instead.
Merge remote-tracking branch 'origin/fix-dangling-reference' into pydata2014