- Some commonly used write methods that are independent of
  the calling context (ie, 2D/3D data, geometry, fields)

- Provide singleton null() for ensightFile, ensightGeoFile.
  Can be used for MPI slaves that need a file reference for their
  methods, but will never write to it, but it is also reasonable
  to use an autoPtr with rawRef() for that as well.

- use explicit names within ensightPTraits

- More informative than a horizonal line, can help when debugging.

STYLE: remove unused write field methods from ensightParts

- regression introduced by ef9a14b2

Related to #132.

Test with #122

- most notably the '%' which is used as a separator in places
  caused problems.

EHN: only use valid ensight file/variable names for writers

- fixed:   foamToEnsightParts, ensightSurfaceWriter
- pending: foamToEnsight

BUG: no geometry written for foamToEnsightParts with moving mesh (fixes #142)

- an incorrect path was causing the issue

- add points/faces constructor to ensightPartFaces with optional
  contiguousPoints flag.

- Remove the now redundantensightPartNonMeshFaces class.

This reverts commit c5bea524.

This reverts commit b18f6cc1.

library:
  * routines for managing cellTable and boundaryRegion
  * writing ensight files and parts
  * mesh reader/writer for STARCD

utils:
  * star4ToFoam
  * foamToStarMesh
  * foamToEnsightParts