Linear bearing "hull" library

Generates "hulls" with caps for linear bearings, lm3,4,5,6,8 and 10 at present,

The module "bearingHull" takes a few arguments, the only one that's required is model which is the numeric reference for the bearing (lm8 = 8 and so on) .

right flips the hull when set to true
angle rotates the cutouts and screw posts around the hull rather than deal with axis changes when rotating after the effect.

full makes the screw posts extend for the entire length of the hull

cutout generats a s