Update to make it work with python3. This translate was done by Dan Clewley, working to finish it off.
Further fixes for py6s. 2to3 now suggests no further changes to files.
Dealt with changes in module locations for urlopen
Switched to using BytesIO rather than StringIO for importing data from URL to numpy
Merge branch 'master' of https://github.com/robintw/Py6S into ToMerge

This brings up to date the Py3 branch with the latest additions from the master

Conflicts:
	Py6S/Params/aeroprofile.py
	Py6S/SixSHelpers/all_angles.py
	Py6S/SixSHelpers/all_wavelengths.py
Fixed print statements for debug report to work with Py3
Fixed another print bug
Fixed Py2/Py3 for importing from URLS
Converted maps to lists for centre wavelengths
Possibly fixed Radiosonde importing from URL on Py3
Updated tox to test on py27 and py33
Fixed parsing of angles from output file - now floats
Made NCAVEO case study Py3 compatible
Added first Geometry test
Updated tox.ini to use sitepackages & fixed issue by adding pip -I
Merge branch 'ToMerge' of https://github.com/robintw/Py6S into ToMerge
Fixed bug when I used assertEqual rather than assertAlmostEqual
Updated CONTRIBUTORS list to add Pete Bunting and Dan Clewley