Hyperspace Jump Sphere for SectorView

# Description:
A simple Hyperspace Jump Sphere for the SectorView screen which displays a sphere with alpha blending and a dot product effect to give it a gradient. The same effect is applied to the disk which bisects it giving a different degree of opacity depending on the angle through it.

# Issues:
It's still not a very good depth effect :(
The naming is probably all wrong for things, it started life as a Fresnel effect but I simplified it greatly and it probably needs renaming.
I'm unsure if I should be setting the depth write/test and alpha blend settings in the SectorView or the material I apply for the effect.

# Summary:
Neato looking effect that seems useful and people seem to like judging by my initial screenshot posts for feedback.
Submitting earlier than I would like due to being totally rundown and mentally thrashed at work lately, going away tomorrow for a week so no commits for a while. Gives people a chance to look at things and make suggestions / trade insults / etc :)

Andy