Key-value array as an argument for middleware() method in routing.

[rw4lll]

On the moment as far as I know it's possible to use two kinds of middleware notation:

• To pass string alias. optionally you can pass also the params:
  ->middleware('middleware1:param1,param2'); . Also it's possible to pass an array of such strings for several middlewares.
• Alternatively it's possible to use full class name via ::class:
  ->middleware(EnsureTokenIsValid::class); . Or you can pass an array of such classes for several middlewares.

The second approach is more convenient I think as it has better support from the IDE side.
But there is a problem here with params. If you want to pass the param with such kind of notation, you have to use some workaround like this: ->middleware(EnsureTokenIsValid::class . ':param1'); Another one downside is that it's possible to pass only string as a param.

I think it would be more convenient to use something like key-value array to pass such params. E.g.:
->middleware([EnsureTokenIsValid::class => $param, SomeOtherMiddleware::class => $param]);
or even this way with several params:
->middleware([EnsureTokenIsValid::class => [$param1, $param2], SomeOtherMiddleware::class => [$param1, $param2]]);

I can make a PR for this feature but would like to ensure it fits by Laravel design.