[Vision] Clean up and refactor spin_steam

[OscarSmiley]

Background

spin_steam.py uses the SpinCamera class to encapsulate PySpin Spinnaker calls into a simpler and cleaner interface. Code was written for a demo but can easily be converted to production utility code. Some areas need to be changed/commented for clarity and simplicity.

Overall goal

Convert cv_demo to production computer vision as it is superior to previous computer vision code

This ticket

Refactor spin_stream.py for clarity. Maybe include new method parameters for colour correction (see spinnaker documents)