Calculate twilights using RiseTransitSetTimes

[andris-zalitis]

See https://github.com/onekiloparsec/SwiftAA/issues/48#issuecomment-284153605

[codecov[bot]]

Codecov Report

Merging #52 into master will decrease coverage by -0.07%. The diff coverage is 100%.

@@            Coverage Diff             @@
##           master      #52      +/-   ##
==========================================
- Coverage    31.7%   31.64%   -0.07%     
==========================================
  Files         226      226              
  Lines       12875    12857      -18     
==========================================
- Hits         4082     4068      -14     
+ Misses       8793     8789       -4

Impacted Files	Coverage Δ
SwiftAA/RiseTransitSet.swift	100% <100%> (ø)	:white_check_mark:
aaplus-v1.76/AADynamicalTime.cpp	9.88% <0%> (-4.49%)	:x:
aaplus-v1.76/AAVSOP87.cpp	42.85% <0%> (-1.33%)	:x:
aaplus-v1.76/AANutation.cpp	86.02% <0%> (-0.98%)	:x:
aaplus-v1.76/AACoordinateTransformation.h	94.73% <0%> (-0.27%)	:x:
aaplus-v1.76/AARiseTransitSet.cpp	96.77% <0%> (+2.58%)	:white_check_mark:

---

Continue to review full report at Codecov.

Legend - Click here to learn more Δ = absolute <relative> (impact), ø = not affected, ? = missing data Powered by Codecov. Last update 1471d10...8a1bc44. Read the comment docs.

[onekiloparsec]

Thanks!