[5.0] Fix CLI Dependencies

Automatically instantiate a Request object if it's required. (Useful when running from the CLI where it would not already be instantiated.)

ServiceProviders using objects (eg. URLGenerator) which depend on a Request object were squaking due to receiving NULL instead of a Request object.

[See here.](https://laracasts.com/discuss/channels/general-discussion/laravel-5-service-provider)
Don't think it going to be enough, mainly because that is there to capture when you're inside a console? It need something similar to how request is resolved in 4.2 (and below).