Replaced most __GNUG__ with __GNUC__

It looks like a typo, but actually isn't.  In C++ files they are
equivalent, but since VTK has 218 occurrences of __GNUC__ and only
8 of __GNUG__, I think it's more consistent and less confusing to
standardize.

Change-Id: Ic7c5facc57cb0cac9a9055d4b708c3f2776167e3
Big find-replace of VTK_LARGE_INTEGER -> VTK_INT_MAX

vtkType.h says that VTK_LARGE_INTEGER is a
'compatibility name'.  There were many uses of the
old name, which I updated.  The find-replace should
be quite safe as it's basically what the preprocessor
does anyway.

Change-Id: Ic82bfec6d706dbcd68af70f2d4a31cdd51f7b497
Big find-replace of VTK_LARGE_FLOAT -> VTK_FLOAT_MAX

vtkType.h says that VTK_LARGE_FLOAT is a
'compatibility name'.  There were many uses of the
old name, which I updated.  The find-replace should
be quite safe as it's basically what the preprocessor
does anyway.

Change-Id: I66ecb51cd2f21ee3cdf9289d8a65d39fc4519a83
Put VTK_LARGE_INTEGER and VTK_LARGE_FLOAT in VTK_LEGACY_REMOVE.

vtkType.h says that VTK_LARGE_INTEGER and VTK_LARGE_FLOAT are
'compatibility names'.  All uses of these names were updated
in previous commits to use the new names, so now wrap them in
VTK_LEGACY_REMOVE.

Change-Id: Ibbf7e9841003432d1fda9b6fd5417182bc387a5c
Merge topic 'fix_bgl_xlc_build_issues' into pv-master

8fe6048 Fix build issues on BG/P.
Merge remote-tracking branch 'pvvtk/pv-master' into HEAD

* pvvtk/pv-master:

Change-Id: Ie7606f193a2473c8d1ab850675f18726c1ecb05f
Merge topic 'GNUG-change' into master

da6ab15e Replaced most __GNUG__ with __GNUC__
Merge topic 'old-vtkType-cleanup' into master

435d5b1f Put VTK_LARGE_INTEGER and VTK_LARGE_FLOAT in VTK_LEGACY_REMOVE.
04d04637 Big find-replace of VTK_LARGE_FLOAT -> VTK_FLOAT_MAX
1ff4b0ee Big find-replace of VTK_LARGE_INTEGER -> VTK_INT_MAX
Fix OpenGL include dependency.

This reverts commit 35a3e376de773d6d98cf5cd8af1b1e74d2629d97.

Instead of adding OPENGL_INCLUDE_DIR to every module that depends on
vtkRenderingOpenGL, we add OPENGL_INCLUDE_DIR as one of the
vtkRenderingOpenGL_INCLUDE_DIRS. That way, any module depending on
vtkRenderingOpenGL will automatically know where to find gl.h since gl.h is
needed by the header files for classes in vtkRenderingOpenGL.

Change-Id: I6675c2b522e15b3fc6f7a80c28f91c56660b671e
Merge topic 'fix_opengl_dependency' into master

ad146c5d Fix OpenGL include dependency.