Adding vertex mode for point cloud shape

[jslee02]

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• Document new methods and classes
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• Set version target by selecting a milestone on the right side
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[codecov]

Codecov Report

Merging #1351 into master will increase coverage by 0.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #1351      +/-   ##
==========================================
+ Coverage   56.88%   56.89%   +0.01%     
==========================================
  Files         366      366              
  Lines       27174    27174              
==========================================
+ Hits        15458    15461       +3     
+ Misses      11716    11713       -3

Impacted Files	Coverage Δ
dart/dynamics/PointCloudShape.hpp	0% <ø> (ø)	⬆️
dart/dynamics/Skeleton.cpp	66.12% <0%> (+0.16%)	⬆️