Some minor cleanup from @brendo's PR with a quick rename

Author: drtriumph

Authentication/JWT.php

@@ -74,7 +74,7 @@ public static function decode($jwt, $key = null, $verify = true)
 
             // Check if the nbf if it is defined.
             if (isset($payload->nbf) && $payload->nbf > time()) {
-                throw new TooEarlyException(
+                throw new BeforeValidException(
                     'Cannot handle token prior to ' . date(DateTime::ISO8601, $payload->nbf)
                 );
             }

Exceptions/BeforeValidException.php

@@ -0,0 +1,6 @@
+<?php
+
+class BeforeValidException extends UnexpectedValueException
+{
+
+}

Exceptions/ExpiredException.php

@@ -3,4 +3,4 @@
 class ExpiredException extends UnexpectedValueException
 {
 
-}
+}

Exceptions/SignatureInvalidException.php

@@ -3,4 +3,4 @@
 class SignatureInvalidException extends UnexpectedValueException
 {
 
-}
+}

Exceptions/TooEarlyException.php

@@ -45,12 +45,12 @@ public function testExpiredToken()
         JWT::decode($encoded, 'my_key');
     }
 
-    public function testTooEarlyToken()
+    public function testBeforeValidToken()
     {
-        $this->setExpectedException('TooEarlyException');
+        $this->setExpectedException('BeforeValidException');
         $payload = array(
             "message" => "abc",
-            "nbf" => time() + 20); // time in the past
+            "nbf" => time() + 20); // time in the future
         $encoded = JWT::encode($payload, 'my_key');
         JWT::decode($encoded, 'my_key');
     }