Improves the handling of residuals from the segregated solution of vectors and tensors.

- allows users to specify target maximum equation intial residuals, and
  stop the run if the conditions are achieved

the origProc and origId or the particle only.

     along sample path

STYLE: Minor code formatting

This data can be used for convergence testing e.g. by a functionObject.
Other data could also be stored, e.g. global continuity errors and other reduced results.

- function object to read fields and register them on the mesh database
  for further post-processing

- moved creation of singlePhaseTransportModel to within RAS/LES model
  construction for incompressible cases

It is not clear that this "correction" term has provided any benefit and there
are cases for which it has proved detrimental to stability and convergence.

planes, rather than a vertex-by-vertex check.  Assesses concavity as
relevant to the tracking.

A cell is concave if there is a face whose face-centre is outside the plane of any other face on the cell.
Another option is to check for any vertices being         outside      ,,    ,,
but this is not consistent with current tracking.

and formulating the enthalpy sources consistently.