Added API listing filtering & cleaned ApiAuthenticate returns

API listing endpoint filter can be found via &filter[name]=my+book query
parameters. There are a range of operators that can be used such as
&filter[id:gte]=4

app/Exceptions/ApiAuthException.php

@@ -2,16 +2,6 @@
 
 namespace BookStack\Exceptions;
 
-use Exception;
+class ApiAuthException extends UnauthorizedException {
 
-class ApiAuthException extends Exception
-{
-
-    /**
-     * ApiAuthException constructor.
-     */
-    public function __construct($message, $code = 401)
-    {
-        parent::__construct($message, $code);
-    }
 }