vips8 binding for Python

This overrides file adds a few small helper functions to the gobject-introspection binding for libvips. It works with python2.7 and python3.4.

There's a chapter in the libvips API docs on these overrides, see "Using libvips from Python".

vips-x.y.z/test has a test suite. Again, the test suite works with python2.7 and python3.4.

Vips.py needs to be in the overrides directory of your gobject-introspection pygobject area, for example:

sudo cp Vips.py /usr/lib/python2.7/dist-packages/gi/overrides

sudo cp Vips.py /usr/lib/python3/dist-packages/gi/overrides