* canvas/reconstruction_on_function.hh: New, this canvas is able to
	compute a reconstruction by dilation or by erosion on a function.
	* reconstructions_on_function.hh: Using this canvas to implement
	reconstructions on function.
	* reconstructions_on_function.cc: New, a test.

	* canvas/reconstruction.hh: Rename as...
	* canvas/reconstruction_on_set.hh: ...this.
	* reconstructions.cc: Rename as...
	* reconstructions_on_set.cc: ...this.
	* reconstructions.hh: Rename...
	* reconstructions_on_set.hh: ...this.

git-svn-id: https://svn.lrde.epita.fr/svn/oln/trunk@3034 4aad255d-cdde-0310-9447-f3009e2ae8c0