Python overhaul: ImageInput (fixes, expose new methods, unit tests, docs)
Also many of the "global" functions and symbols have been overhauled.
Python overhaul: ImageOutput (fixes, expose new methods, unit tests, docs)
Rebuild PDF docs
Merge pull request #667 from lgritz/lg-python

Python overhaul: ImageInput & ImageOutput (fixes, expose new methods, unit tests, docs)