ENH: Refine modular tree layout

Since modularization commit 7b16d242 (Transition from monolithic to
modular ITK, 2011-03-10) the directory structure storing modules is
independent of the build files and module names.  After some experience
with the modularized tree layout we have decided to rename the directory
containing the modules:

  ITK/          -> Modules/
  ITK/Utilities -> Modules/ThirdParty

Rename the files without modification to preserve enough information for
"git blame -M" and "git log --follow" to connect moved files to their
old location and history.
MetaIO: Avoid requiring parent projects to provide "../metaIOConfig.h"

Configure our own "metaIOConfig.h" in the build tree with the same
content that would be provided by ITK or VTK parent projects.
MetaIO: Add missing include <stddef.h> for ptrdiff_t

Fixes error "ptrdiff_t was not declared in this scope".

Author: David Doria <daviddoria@gmail.com>
Change-Id: I1e0dee67d26681f4119ac1fd00ecec3d139eb726
BUG: MetaImage data file was missing path.

When writing ROIs the filename of the data was missing the path that
should make it be stored in the same directory as the header file.

Also unified the hard-coded size of buffers used to store path names.
They are now using a common MAXPATHLENGHT defined symbol set to 2048.

Change-Id: If6922e5676df8539bffe894cab514e08f7ade9e3
COMP: added delete statements on error paths as suggested by cppcheck
COMP: added const to read-only access methods
ENH: Add metaObject for FEM data
COMP: Add const access methods to metaFEMObject
STYLE: remove tabs and delete trailing whitespace
BUG: was writing out undeformed state local coordinates where deformed were needed
BUG: plug memory leaks in FEMObject
BUG: fix memory allocation issues
BUG: fix memory allocation issues
BUG: silence shadowed variable warning
STYLE: Reformatting + turning off execute bit in file permissions
COMP: remove possible null pointer dereference
COMP: Remove compiler warning in metaFEMObject
COMP: got rid of warnings
COMP: allow CMake project name to be overridden, to avoid project name collissions when built inside ITK
COMP: Remove unused variables
COMP: cleanup based on CLang warnings