Vector debugging commands.

[raven1934]

Long time e2 user and a clumsy mathguy here, I use vectors a lot on my projects and I think even if I've improved it would still be a reasonably useful feature for e2 to have debugging linedraw/shapedraw functions for vectors... I'm unsure if this could be just isolated clientside/optionally shared to server/others but I definetly can say in my own cases this would be a great help.