Star.distance() values look wrong

[CyberiaResurrection]

Can't remember where/when I first noticed the forward/reverse mismatch, but noting down here for reference.

Forward distance is the result of calling starA.distance(starB), and reverse distance is the result of calling starB.distance(starA). Manual distance is from manually counting the distance between A to B.

At the very least, a distance value should be independent of direction (ie, whatever the forward and reverse distances are between a given pair of stars, they should be equal). Distance values should also be invariant under translation - shifting the start and endpoints by the same amount shouldn't change the distance value.

Star A	Star B	Forward Distance (pc)	Reverse Distance (pc)	Manual Distance (pc)
Core 0104	Core 2209	37	37	21
Lishun 0104	Lishun 2209	37	37	21
Core 0105	Core 0525	26	26	22
Vland 0105	Vland 0525	26	26	22
Core 0205	Core 1315	25	25	15
Dagudashaag 0205	Dagudashaag 1315	25	25	15
Core 0204	Core 1215	25	26	16
Zarushagar 0204	Zarushagar 1215	25	26	16
Core 0105	Core 1216	28	28	17
Massilia 0105	Massilia 1216	28	28	17
Core 0204	Core 2208	33	34	20
Delphi 0204	Delphi 2208	33	34	20
Core 0204	Core 0725	28	28	23
Fornast 0204	Fornast 0725	28	28	23
Core 0105	Core 2210	37	37	21
Antares 0105	Antares 2210	37	37	21
Core 0910	Core 1407	5	5	5
Core 0910	Core 1507	6	6	6
Core 0910	Core 1412	10	10	5
Core 0910	Core 1513	12	11	6
Core 0910	Core 0914	5	4	5
Core 0910	Core 0915	6	5	6
Core 0910	Core 1410	8	8	5
Core 0910	Core 1510	9	6	6

[CyberiaResurrection]

Updated table after latest pushes as at this writing:

Asterisked values have been changed by commits in attached PR

Star A	Star B	Forward Distance (pc)	Reverse Distance (pc)	Manual Distance (pc)
Core 0104	Core 2209	37	37	21
Lishun 0104	Lishun 2209	37	37	21
Core 0105	Core 0525	26	26	22
Vland 0105	Vland 0525	26	26	22
Core 0205	Core 1315	25	25	15
Dagudashaag 0205	Dagudashaag 1315	25	25	15
Core 0204	Core 1215	26*	26	16
Zarushagar 0204	Zarushagar 1215	26*	26	16
Core 0105	Core 1216	28	28	17
Massilia 0105	Massilia 1216	28	28	17
Core 0204	Core 2208	34*	34	20
Delphi 0204	Delphi 2208	34*	34	20
Core 0204	Core 0725	28	28	23
Fornast 0204	Fornast 0725	28	28	23
Core 0105	Core 2210	37	37	21
Antares 0105	Antares 2210	37	37	21
Core 0910	Core 1407	5	5	5
Core 0910	Core 1507	6	6	6
Core 0910	Core 1412	10	10	5
Core 0910	Core 1513	12	12*	6
Core 0910	Core 0914	5	5*	5
Core 0910	Core 0915	6	6	6
Core 0910	Core 1410	8	8	5
Core 0910	Core 1510	9	9*	6

[CyberiaResurrection]

51 has been merged, fixing the underlying wonkiness.