the include file back to mathematicalConstants.H to make upgrading code slightly easier.

Conflicts:
	src/autoMesh/autoHexMesh/trackedParticle/trackedParticle.H
	src/mesh/autoMesh/autoHexMesh/trackedParticle/trackedParticle.H
	src/mesh/blockMesh/blockMesh/blockMeshMerge.C
	src/postProcessing/functionObjects/field/streamLine/streamLineParticle.H

- added subsetStrings and inplaceSubsetString

- added class wordReListMatcher to wrap a match() for a UList<wordRe>

- also sifted through code to find out why polySplineEdge is going wrong

  It doesn't seem to be a virtual/non-virtual issue, but appears to
  be an issue with how BSpline is solving for the new points.

- first version. Only uses simple hex shapes for the blocks.

- expose point field throughout

- make output less verbose, but can switch on/off with verbose() static method