Merge from Philippe Lagadec’s OleFileIO_PL fork

This includes the changes done at <https://bitbucket.org/decalage/olefileio_pl>, migrated from Mercurial to Git. I merged these changes with current Pillow and also fixed up support for Python 3.

Philippe’s README.md has been moved to PIL/OleFileIO-README.md. The other readme files, in HTML and Restructured Text format, are gone, because they seemed to be equivalent to the Markdown one.

Philippe’s license file is also removed, since the same license text is already in the OleFileIO.py file and the readme file. Finally, Philippe’s setup and install scripts are also removed. All of his other changes should be there.