message: das.cli: minor simplification
  The option parsing for loop is now simpler, so we can factor the
  iterator incrementation.
diff: @@ -624,7 +624,7 @@ namespace elle
  ELLE_TRACE_SCOPE("parsing option %s", Symbol::name());
  ELLE_DUMP("remaining arguments: %s", args);
  for (auto it = next_option(args.begin()); it != args.end();
  - it = next_option(it))
  + it = next_option(it + 1))
  {
  // There's a possible explicit argument after `=`.
  auto const eq = it->find('=');
  @@ -647,12 +647,11 @@ namespace elle
  {
  // `--foo`: no `=`.
  *it = nothing();
  - ++it;
  - if (it != args.end() && !is_option(*it, opts) && *it != nothing())
  + if (it+1 != args.end() && !is_option(*(it+1), opts) && *(it+1) != nothing())
  {
  + ++it;
  argument_set(*it);
  *it = nothing();
  - ++it;
  }
  else
  {
  @@ -669,15 +668,8 @@ namespace elle
  // `--foo=bar`: explicit argument.
  argument_set(it->substr(eq + 1));
  *it = nothing();
  - ++it;
  }
  }
  - else
  - {
  - // This is not the option we were looking for. Skip
  - // it.
  - ++it;
  - }
  }
  elle::meta::static_if<std::is_base_of<CLI_Symbol, Symbol>::value>(
  [] (auto& pos, auto t)
  