Add retimePathWithKunz to Robot

[gilwoolee]

This PR adds retimeWithKunz method to Robot class and its derived classes. In the near future, we should replace this with a more general retimer (Issues #504, #477 ).

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[codecov]

Codecov Report

Merging #505 into master will decrease coverage by 0.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #505      +/-   ##
==========================================
- Coverage   77.66%   77.65%   -0.02%     
==========================================
  Files         262      262              
  Lines        6784     6784              
==========================================
- Hits         5269     5268       -1     
- Misses       1515     1516       +1

Impacted Files	Coverage Δ
src/planner/ompl/CRRT.cpp	75.58% <0%> (-0.59%)	⬇️