Generate a alloc-instance + init-attributes

Property definitions

nitc $ JavaCompilerVisitor :: init_instance
	# Generate a alloc-instance + init-attributes
	fun init_instance(mtype: MClassType): RuntimeVariable do
		var rt_name = mtype.mclass.rt_name
		var res = new_expr("new RTVal({rt_name}.get{rt_name}())", mtype)
		generate_init_attr(self, res, mtype)
		return res
	end
src/compiler/java_compiler.nit:946,2--952,4