Changed "flex++" to "flex --c++" to avoid the need to create the link from "flex" to "flex++" after installing "flex".

Moved the construction of the static "null" strings to stringsGlobals.C which is included in global.Cver to avoid inter-dependency problems in the construction of globals.

Patch supplied by Michael Wild, see
http://openfoam.cfd-online.com/cgi-bin/forum/show.cgi?126/10442

    warning: use of old-style cast

http://openfoam.cfd-online.com/cgi-bin/forum/show.cgi?126/10427

- if local repo is up to date, HEAD and origin/HEAD are the same
  so id was returned twice

    - added pdFinal option
    - labelled muf - grad(muf) used, so can now manipulate in fvSolution etc
    - added absolute/relative around the calculation of divU

- version is WM_PROJECT_VERSION prefix + SHA1 from current git head
- move double quotes from make rules to global.Cver for extra safety

- added wmakePrintBuild -check, -update, -version options
- only update .build cache when explictly requested and
  from within the wmake Cver rules
- use -check option to avoid unnecessary remake in src/Allwmake

- the $WM_PROJECT_DIR/.build file is automatically updated.
  This file is (and must be) ignored by git.

- This was originally plan 'B', but it is actually probably more efficient
  than using PtrDictionary anyhow.
- straightened out the return value logic, but it wasn't being used anywhere
  anyhow.
- new 'updated_' data member avoids inadvertent execution in the read()
  method when execution is turned off.

Conflicts:

	src/Allwmake
	src/OpenFOAM/global/global.C
	wmake/rules/General/version

Retained solution with global.Cver

- move url to lower right: makes version information stand out better

New fuels are iso/n-propanol and urea.  Although urea is a bit dodgy, but that's
all of the properties Ive found so far.

I've also added a variation of temperature instead of constant temperature for
some injector-classes so Im sending you the new version of the dieselFoam
tutorial also.

- PtrDictionary and remove(const word&) does not seem to work