import { Command } from "https://deno.land/x/license@1.0.3/deps/cmd.ts";
Parse options from argv
removing known options,
and return argv split into operands and unknown arguments.
Examples:
argv => operands, unknown --known kkk op => [op], [] op --known kkk => [op], [] sub --unknown uuu op => [sub], [--unknown uuu op] sub -- --unknown uuu op => [sub --unknown uuu op], []