Feature/edits - draft tutorials Forces, controlling audio, using lights V1, V2 and V3

have updated resolutions, note some of the text is a note to myself, (usually stuff in bold italics).

Lights V1 is based on Will's setup. V2 has the more fancy control scheme (with
bracket notation to access light['color']['b'] etc.  V3 is simple
cycling through RGB values with R, G, B keys.

What's a torque. Could do with a bit of explanation here.