* mln/canvas/morpho/attribute_filter.hh: Move
	algebraic/leveling facade from attribute filter and change dispatch.
	* mln/canvas/morpho/connected_filter.hh: Remove.
	* mln/morpho/algebraic_filter.hh: Facade for algebraic filter.
	* mln/morpho/closing: New.
	* mln/morpho/leveling_filter.hh: Facade for leveling filter.
	* mln/morpho/opening: New.
	* sandbox/edwin/tree/propagate.hh
	* sandbox/edwin/tree/tree.cc: Correct some bugs.
	* tests/canvas/morpho/attribute_filter.cc: Test file for
	attribute filters.
	* tests/canvas/morpho/connected_filter.cc: Remove.

git-svn-id: https://svn.lrde.epita.fr/svn/oln/trunk@3435 4aad255d-cdde-0310-9447-f3009e2ae8c0