Major optimization of Octree module

[Pyseph]

Notably;

• This version of the module is now roughly 0.3x more performant.
• Swapped out t[#t+1] to table.insert
• Removed redundant, 1-time use variables
• No longer calling functions but rather calculating directly (possible issues with ease-of-use in terms of changing function behavior, but this also allows for much faster run times)
• Localization of table indices

[Anaminus]

A benchmark of current (Octree) versus optimized (PyOctree) shows the following performance improvements:

Radius	Octree	PyOctree	Improvement
20	26304	23169	1.13x faster
40	47895	39960	1.19x faster
60	82806	65281	1.26x faster
80	132882	104087	1.27x faster
100	192587	147095	1.30x faster
120	277387	207931	1.33x faster
140	374498	273656	1.36x faster
160	519923	372003	1.39x faster
180	661866	485274	1.36x faster
200	834977	625786	1.33x faster
220	1076302	838082	1.28x faster
240	1276984	937616	1.36x faster
260	1595419	1068181	1.49x faster
280	1815949	1256723	1.44x faster
300	2100269	1421281	1.47x faster
320	2346557	1710521	1.37x faster
340	2702164	1851038	1.45x faster
360	2870727	2204199	1.30x faster
380	3182624	2275747	1.39x faster
400	3393377	2665696	1.27x faster
420	3663764	2857884	1.28x faster
440	3909860	3156822	1.23x faster
460	4110152	3032455	1.35x faster
480	4331064	3217508	1.34x faster
500	4342197	3453817	1.25x faster

[howmanysmall]

This can be made faster at the cost of the readability.

(I'm not good with Excel so my charts are not very good, sorry)

[Pyseph]

A benchmark of current (Octree) versus optimized (PyOctree) shows the following performance improvements:

Radius Octree PyOctree Improvement 20 26304 23169 1.13x faster 40 47895 39960 1.19x faster 60 82806 65281 1.26x faster 80 132882 104087 1.27x faster 100 192587 147095 1.30x faster 120 277387 207931 1.33x faster 140 374498 273656 1.36x faster 160 519923 372003 1.39x faster 180 661866 485274 1.36x faster 200 834977 625786 1.33x faster 220 1076302 838082 1.28x faster 240 1276984 937616 1.36x faster 260 1595419 1068181 1.49x faster 280 1815949 1256723 1.44x faster 300 2100269 1421281 1.47x faster 320 2346557 1710521 1.37x faster 340 2702164 1851038 1.45x faster 360 2870727 2204199 1.30x faster 380 3182624 2275747 1.39x faster 400 3393377 2665696 1.27x faster 420 3663764 2857884 1.28x faster 440 3909860 3156822 1.23x faster 460 4110152 3032455 1.35x faster 480 4331064 3217508 1.34x faster 500 4342197 3453817 1.25x faster

Ahh, my bad - my radii search speeds went down from 0.6 to 0.2ms, and I thought it was a 3x improvement since 6/2=3.. forgot you need to do it the other way around.. oops