Implement a fixed spread pattern, for (OK) Shotgun (Crylink and Hagar share the function call also)

Balance changes have been extracted to drjaska/spread-pattern-balance.

Fixed spread pattern generation has been tweaked slightly to allow for more spread patterns. Shotgun and OK Shotgun are the only weapons which have these for now. Hopefully next release will also allow them for Crylink and maybe Hagar.

I simplified shockwave's overcomplicated formula for drawing the cone which I could not see any difference on some side. The cone used to be rotated by having its starting point rotated by a magic number but doesn't anymore. This should currently have no effect as a micro-optimization but can be rolled back if there is a change.

Shotgun spread comparisons with default 0.12 spread

Old	New (with spread / 1.5)

Spread pattern changes between patterns 1 and 2

(Increased spread at a point to separate decals)

Old	New
1	1
2	2
3	3
4	4
5	5
6	6
7	7
8	8
9	9
10	10
11	11
12	12
13	13