[5.4] Use the correct user model namespace in make:policy Command

[Lloople]

I've been creating new policies this days in a project where my models are under app/Models directory.

Every policy I created I needed to modify the namespace of the user's model.

I remembered that this information is available through the auth configuration file and ended up with this.

I want to thank @JosephSilber who taught me a lot on this Gates & Policies stuff.

[ntzm]

@return string mixed isn't valid, should be just @return string

[Lloople]

Thanks, didn't notice that

[taylorotwell]

Hard-coding App will not work if people have changed the namespace of their application.

[Lloople]

@taylorotwell Right, working on a fix

[4refael]

A slight improvement

if ($this->rootNamespace().'User' !== config('auth.providers.users.model')) {
	return str_replace($this->rootNamespace().'User', config('auth.providers.users.model'), $stub);
}
return $stub;