Add support for maximal elongations of Mercury and Venus

[Deuchnord]

Q	A
Bug fix?	no
New feature?	yes
Related issues	Fix #49
Has BC-break	no
License	GNU AGPL-v3

[codecov]

Codecov Report

Merging #53 into features will increase coverage by 0.38%.
The diff coverage is 90.14%.

@@             Coverage Diff              @@
##           features      #53      +/-   ##
============================================
+ Coverage     81.88%   82.27%   +0.38%     
============================================
  Files             8        8              
  Lines           508      536      +28     
  Branches         81       88       +7     
============================================
+ Hits            416      441      +25     
  Misses           77       77              
- Partials         15       18       +3

Impacted Files	Coverage Δ
kosmorrolib/core.py	96% <ø> (+5.09%)	⬆️
kosmorrolib/events.py	100% <100%> (ø)	⬆️
kosmorrolib/ephemerides.py	53.63% <66.66%> (-1.51%)	⬇️
kosmorrolib/data.py	88.39% <90%> (+0.23%)	⬆️

---

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 410c553...9dbc093. Read the comment docs.