Update package.xml and README.md for 3.0.0 release

Author: robertdimarco

README.md

@@ -65,6 +65,18 @@ $decoded = JWT::decode($jwt, $key, array('HS256'));
 Changelog
 ---------
 
+#### 3.0.0 / 2015-07-22
+- Minimum PHP version updated from `5.2.0` to `5.3.0`.
+- Add `\Firebase\JWT` namespace. See
+[#59](https://github.com/firebase/php-jwt/pull/59) for details. Thanks to
+[@Dashron](https://github.com/Dashron)!
+- Require a non-empty key to decode and verify a JWT. See
+[#60](https://github.com/firebase/php-jwt/pull/60) for details. Thanks to
+[@sjones608](https://github.com/sjones608)!
+- Cleaner documentation blocks in the code. See
+[#62](https://github.com/firebase/php-jwt/pull/62) for details. Thanks to
+[@johanderuijter](https://github.com/johanderuijter)!
+
 #### 2.2.0 / 2015-06-22
 - Add support for adding custom, optional JWT headers to `JWT::encode()`. See
 [#53](https://github.com/firebase/php-jwt/pull/53/files) for details. Thanks to

package.xml

@@ -19,10 +19,10 @@
   <email>[email protected]</email>
   <active>yes</active>
  </lead>
- <date>2015-06-22</date>
+ <date>2015-07-22</date>
  <version>
-  <release>2.2.0</release>
-  <api>2.2.0</api>
+  <release>3.0.0</release>
+  <api>3.0.0</api>
  </version>
  <stability>
   <release>beta</release>