Resolves bug-report http://www.openfoam.org/mantisbt/view.php?id=1573

Provided by Bruno Santos
Also some general cleaning and update of comment.
Resolves bug-report http://www.openfoam.org/mantisbt/view.php?id=1167

Tested with snapshot gcc-5-20150215.tar.bz2

classes in the DebugSwitches sub-dictionary of system/controlDict

Resolves bug-report http://www.openfoam.org/mantisbt/view.php?id=1432

wrmo: Add -a/-all/all option to remove .o files from all platforms rather than just the current platform.

Description
    Remove all .o files from the object directory tree corresponding to the
    current source derectory or remove only the .o file corresponding to the
    optionally specified [file].

Resolves bug-report http://www.openfoam.org/mantisbt/view.php?id=1485

Resolves bug-report http://www.openfoam.org/mantisbt/view.php?id=1483

Remove all .dep files from the object directory tree corresponding to the
current source derectory or remove only the .dep files referring to the
optionally specified [file].

To compile with 64bit labels set

WM_LABEL_SIZE=64

in ~/OpenFOAM/dev/prefs.sh

source ~/.bashrc

then Allwmake in OpenFOAM-dev.

This will build into for example OpenFOAM-dev/platforms/linux64ClangDPInt64Opt

If WM_LABEL_SIZE is unset or set to 32:

WM_LABEL_SIZE=32

the build would be placed into OpenFOAM-dev/platforms/linux64ClangDPInt32Opt

Thus both 32bit and 64bit label builds can coexist without problem.

Resolves bug-report http://www.openfoam.org/mantisbt/view.php?id=1222

i.e. wmake searches up the directory tree to find the Make directory if it is not
in the current directory.

dwim (do what I mean): search up directories tree for Make sub-directory and build the target
    specified in Make/files