* tests/core/alias/dpoint2d.cc: Exercise the substraction of a
	dpoint2d from a point2d.
	* tests/core/alias/neighb2d.cc: New.
	* tests/core/alias/Makefile.am (check_PROGRAMS): Add neighb2d.
	(neighb2d_SOURCES): New.
	* tests/io/dump/dump.cc: Exercise mln::io::dump::load and
	mln::io::dump::save with 3D binary images.
	* tests/io/dump/Makefile.am (MOSTLYCLEANFILES):
	Add dump-bool-3d.dump
	* tests/value/int_u32.cc: New test (known to fail).
	* tests/value/Makefile.am (check_PROGRAMS): Add int_u32.
	(int_u32_SOURCES): New.
	(XFAIL_TESTS): New.
	Add int_u32.