* mln/io/all.hh: update.

	* mln/io/fits/load.hh,
	* mln/io/pbm/load.hh,
	* mln/io/pbm/save.hh,
	* mln/io/pfm/load.hh,
	* mln/io/pfm/save.hh,
	* mln/io/pgm/load.hh,
	* mln/io/pgm/save.hh,
	* mln/io/pnm/save.hh,
	* mln/io/ppm/load.hh,
	* mln/io/ppm/save.hh: Update copyright.

	* mln/io/txt/save.hh: save an image<char> to a txt file.

	* mln/io/off/all.hh,
 	* mln/io/txt/all.hh: new missing 'all' headers.

git-svn-id: https://svn.lrde.epita.fr/svn/oln/branches/cleanup-2008@2793 4aad255d-cdde-0310-9447-f3009e2ae8c0