* img/test.fits:
	  a fits image

	* mln/io/internal:
		The functions to save and load ppm, pbm and pgm format
		looked quite similar. I add this directory to factorise
		all these similarities

	* mln/io/internal/abort.hh:
		the abort function used in loading functions
	* mln/io/internal/pnm/load.hh:
		functions to load pnm files, 8 or 16 bits.
	* mln/io/internal/pnm/load_header.hh:
		function to read a pnm header.
	* mln/io/internal/pnm/macros.hh:
		Some macros to identify the magic numbers of the formats
	* mln/io/internal/pnm/save.hh:
		functions to load pnm files, 8 or 16 bits.
	* mln/io/internal/pnm/save_header.hh:
		function to save a pnm header.

	* mln/io/internal/pnm:
		all internal treatments of pnm format, used by
		concrete formats (pbm, pgm, ppm)

	* mln/io/pbm/load.hh:
		loading of pbm format done
	* mln/io/pbm/save.hh:
		saving of pbm format done

	* mln/io/pfm/load.hh:
		loading of pfm format done

	* mln/io/pgm/load.hh:
		loading of pgm format done
	* mln/io/pgm/save.hh:
		saving of pgm 8/16 bits format done

	* mln/io/ppm/load.hh:
		loading of ppm 8/16 bits format done
	* mln/io/ppm/save.hh:
		loading of ppm 8/16 bits format done

	* mln/value/rgb.hh:
		To fix : we can't apply level:transform on rgb images
		   convert_< rgb8 > could be one part of the problem.

	* mln/value/rgb16.hh:
		add rgb16 type to test ppm 16bits

	* tests/io_pbm.cc:
		some tests
	* tests/io_pgm.cc:
		some tests
	* tests/io_ppm16.cc:
		some tests

git-svn-id: https://svn.lrde.epita.fr/svn/oln/trunk@1109 4aad255d-cdde-0310-9447-f3009e2ae8c0