- ditched PrimitivePatchExtra in favour of a PatchTools class that is
  currently just a collection of static functions. They could equally well
  live within PrimitivePatch itself, but isolated also has its advantages.

- MeshedSurface, UnsortedMeshedSurface now have 'regions' instead of
  'patches' since they are more like a faceZone for meshed surfaces than
  patches. This might avoid confusion at a later stage.

- new members:  capacity(), two-argument resize()/setSize(), const storage()
- new static members: max_value(), packing(), etc.

- can use 'XX.empty()' instead of 'XX.size() == 0', 'XX.size() < 1' or
  'XX.size() <= 0' or for simpler coding.
  It also has the same number of characters as '!XX.size()' and /might/ be
  more readable

- many size checking had 'XX.size() > 0', 'XX.size() != 0', or 'XX.size() >= 1'
  when a simple 'XX.size()' suffices

- The capitalization is consistent with most other template classes, but
  more importantly frees up xfer() for use as method name without needing
  special treatment to avoid ambiguities.

  It seems reasonable to have different names for transfer(...) and xfer()
  methods, since the transfer is occuring in different directions.
  The xfer() method can thus replace the recently introduced zero-parameter
  transfer() methods.
  Other name candidates (eg, yield, release, etc.) were deemed too abstract.

  - added boundBox(const tmp<pointField>&) constructor for use with
    coordinate systems
  - moved some methods from treeBoundBox to boundBox and use VectorSpace ops

- moved findStrings from stringList to new stringListOps
  (helps reduce the influence on dependencies)
- findStrings can also do partial matches

 - operator+=  : add in the listed keys
 - operator-=  : remove the listed keys
 - operator&=  : intersection of keys
 - added xfer constructor (just in case)
 - moved labelHashSet typedef to HashSet.H, for consistency with the
   wordHashSet typedef being there and since it is used so often

- drop copy components constructors in favour of the xfer versions. Even if
  the caller sends through constant data, if will be automatically promoted
  to xfer (via a copy operation).

- use xfer form for calls to resetPrimitives