Fix broken specs.
Tests for perfectGEO.
perfectGEO uses cartesian coords.
ECR module.
Stylistic change.
D type for convenience.
More ECR specs.
Fix ecrToECISV numerics. Specs.
GMST using only UT1. ERA and GMST tests vs AsA2009.
Use gmst' instead of greenwichRA.
TODOs.
Fix tests.
Better numerics for ERA.
Change fractionalPart to interval (-1,1).
Comment re use of fractionalPart in eccentricity tests.
Add zeroTau = zeroTwoPi.
Use tau instead of 2 pi in test cases.
Use tau.
Add comment on GMST and Soop Table 1.
j2000' and sinceJ2000'.