Order nodes counterclockwise for each face in Draco_Mesh::Layout.

[RyanWollaeger]

Background

• In 2D, it is simpler to assume rotation-ordered face-node pairing in Draco_Mesh::Layout.
  • For instance, it is easier to determine orientation of a normal vector to a face.
• Since the X3D and RTT mesh file parsers preserve counterclockwise node ordering in 2D, the generation of the connectivity data (for instance, cell-to-cell linkage) can be made somewhat less computationally complex.

Purpose of Pull Request

• Keep node ordering in generation of [cell, side, ghost cell]-node vector pairs, where vector is subscripted by cell-local face index (which simplifies generation of mesh connectivity data in 2D).
• Add some missing comment documentation for functions arguments in Draco_Mesh.cc and X3D_Draco_Mesh_Reader.i.hh
• Fixes Issue Fix autodoc issues wrt mesh package #524

Description of changes

• Generate Draco_Mesh Layouts assuming rotation-ordered node pairs.
• Add missing parameter descriptions needed by autodoc (issue 524).

Status

• Reference:
  • Pre-Merge Code Review
  • CDash Status
• Checks
  • Travis CI checks pass
  • Code coverage does not decrease
  • Valgrind test passes
  • Toss3 checks pass
  • Trinitite checks pass
  • Code reviewed/approved, sufficient DbC checks, testing, documentation

[codecov]

Codecov Report

Merging #550 into develop will decrease coverage by <.1%.
The diff coverage is 100%.

@@            Coverage Diff            @@
##           develop    #550     +/-   ##
=========================================
- Coverage     93.3%   93.3%   -0.1%     
=========================================
  Files          376     376             
  Lines        17685   17681      -4     
=========================================
- Hits         16504   16500      -4     
  Misses        1181    1181

[codecov]

Codecov Report

Merging #550 into develop will decrease coverage by <.1%.
The diff coverage is 100%.

@@            Coverage Diff            @@
##           develop    #550     +/-   ##
=========================================
- Coverage     93.3%   93.3%   -0.1%     
=========================================
  Files          376     376             
  Lines        17685   17681      -4     
=========================================
- Hits         16504   16500      -4     
  Misses        1181    1181