ENH: snappyHexMesh: add buffer layers before snapping

Summary

Adding buffers layers before adding layers.

Details of new models (If applicable)

snappyHexMeshDict has a top-level entry describing the type of meshing:

// Type of mesh generation:
//  - castellated (default)
//  - castellatedBufferLayer
type            castellatedBufferLayer;

See e.g. tutorial mesh/snappyHexMesh/rotated_block

Risks

With default setting there should be no change in the mesh generation. Only if the face-splitting during snapping (nFaceSplitInterval) is used are there slight differences due to a fix in the logic.

assigned to @andy

added 64 commits

• 10617aea...59c74e53 - 22 commits from branch develop
• 59c74e53...590b7b40 - 32 earlier commits
• c4c2252a - ENH: snappyHexMesh: small improvements
• 98fb2af9 - ENH: snappyHexMesh: parallel consistent intrusion
• 853feba9 - STYLE: remove old usuned code
• d09e5910 - ENH: pointSmoother: add mesh quality checking
• c2360eea - ENH: fvGeometryScheme: use with external points
• b7c7037f - ENH: pointSmoothers: added new smoothers
• a46c582a - ENH: tutorial: demo smoothing
• 57a5094f - ENH: motionSolver: work with bcs
• de8f095e - ENH: README: explanation
• 2f873435 - GIT: incorrect merge

Compare with previous version

added 44 commits

• 2f873435...e7cf8a1d - 2 commits from branch develop
• e7cf8a1d...245e8786 - 32 earlier commits
• 5afe78ec - ENH: snappyHexMesh: small improvements
• 51556051 - ENH: snappyHexMesh: parallel consistent intrusion
• cb9c5126 - STYLE: remove old usuned code
• 47540497 - ENH: pointSmoother: add mesh quality checking
• 8c2a975c - ENH: fvGeometryScheme: use with external points
• e7ebb5cd - ENH: pointSmoothers: added new smoothers
• ef9778e0 - ENH: tutorial: demo smoothing
• 528c9825 - ENH: motionSolver: work with bcs
• f6e1747c - ENH: README: explanation
• 59e443f1 - GIT: incorrect merge

Compare with previous version

changed title from ENH: snappyHexMesh: per faceZone whether to add layers. WIP to ENH: snappyHexMesh: add buffer layers before snapping

assigned to @Mattijs and unassigned @andy

mentioned in commit ab30b030

merged