Fix bugs, add hooks for tracing convergence.

	* green/mln/clustering/kmean1d.hh: Evict k parameter from template
	and replace it by a constructor parameter. Add printing for debugging.
	* green/mln/clustering/kmean1d.hh (update_variance): Fix bugs.
	* green/mln/clustering/kmean1d.hh
	(build_all_dbg, build_mean_dbg, update_cnv, finalize_cnv): New methods.
	* green/mln/clustering/kmean1d.hh (launch_one_time): Fix bugs.
	* green/mln/clustering/kmean1d.hh (launch_n_times): Add hooks.

	Do some works for managing shell parameters while executing the binary.

	* green/demo/clustering/kmean1d/kmean1d.cc
	(main, char_to_string, char_to_unsigned, demo, do_demo): New methods.

git-svn-id: https://svn.lrde.epita.fr/svn/oln/trunk@4564 4aad255d-cdde-0310-9447-f3009e2ae8c0