Python3

I've mergedthe python3 branch from @smaret with a python3 branch in the nolta area.  I fixed the problems with the c extension and some minor python3 issues. This is now in the python3 branch in this repo.

All examples run in both python2 and python3, although I do not have a python2.6 with which to compare.  And I don't have windows to check that.

Please give it a try.