Property definitions

nitc $ MProperty :: _c_name
	redef var c_name is lazy do
		# FIXME use `namespace_for`
		return "{intro_mclassdef.mmodule.c_name}__{intro_mclassdef.mclass.name.to_cmangle}__{name.to_cmangle}"
	end
src/model/model.nit:2185,2--2188,4