TS map calculator update and docs

Modified command line tool to work with different pixels sizes. Added some documentation and brief tutorial.
Always use the print function so that this works with Python 2 and 3.

Maybe a `result.info()` or a nice `print(result)` by implementing some summary info in `info` or `__str__` would be nice?
(e.g. how many pixels were fitted, how many cash evaluations, maybe even print min / max of the arrays)
Obviously this is not needed if you don't want to spend time on this.