Issue with the regeneration of Installation/include/CGAL/license/

[lrineau]

Issue Details

In Installation/include/CGAL/license/README.md, one can read:

cgal/Installation/include/CGAL/license/README.md

Lines 1 to 3 in 94d4555

	To generate the `PACKAGE.h` files, from the file `gpl_package_list.txt`:
	cmake -P generate_files.cmake

I tried that to create a new license header file for a new package (see #8186) and the result, starting from a clean workdir of cgal/master, was a big diff, see https://gist.github.com/lrineau/5271666984da974d23daabcee09e63a7

There are parts of the diff that show that the script generate_files.cmake is actually wrong:

part 1:

index 854b366ba54..ebd2bf82ac4 100644
--- a/Installation/include/CGAL/license/Polygon_mesh_processing/locate.h
+++ b/Installation/include/CGAL/license/Polygon_mesh_processing/locate.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2019  GeometryFactory SARL (France).
+// Copyright (c) 2016  GeometryFactory SARL (France).
 // All rights reserved.
 //
 // This file is part of CGAL (www.cgal.org)

part 2:

@@ -33,8 +29,8 @@
 
 #    ifdef CGAL_LICENSE_ERROR
 #      error "Your commercial license for CGAL does not cover this release \
-of the Polygonal Surface Reconstruction package. \
-You get this error, as you defined CGAL_LICENSE_ERROR."
+              of the Polygonal Surface Reconstruction package. \
+              You get this error, as you defined CGAL_LICENSE_ERROR."
 #    endif // CGAL_LICENSE_ERROR
 
 #  endif // CGAL_POLYGONAL_SURFACE_RECONSTRUCTION_COMMERCIAL_LICENSE < CGAL_RELEASE_DATE

1. The copyright year should not be hard-coded to 2016.
2. The "red" version is right, otherwise the error message triggered by #error contains spurious sequences of spaces.