Be more careful about Joomla! trademark usage

Since the JED Entries checklist makes a big point about trademark usage,
go the extra mile to make sure we are clear.  Remove unnecessary uses of
Joomla! and make it clear that this is the "Mailbox Authorization Plugin
for Joomla!" rather than "Joomla! Mailbox Authorization Plugin".

Signed-off-by: Kevin Locke <klocke@digitalenginesoftware.com>

INSTALL.txt

@@ -1,8 +1,8 @@
 Installation Instructions
 =========================
 
-To install this Joomla! extension, use the following procedure:
-1.  Login to the Administrator interface for the target Joomla! installation
+To install this extension, use the following procedure:
+1.  Login to the Administrator interface for the target installation
     at <http://example.com/administrator>
 2.  Click on Extensions->Install/Uninstall
 3.  Upload the original ZIP file for this component (the file which contained
@@ -11,5 +11,5 @@ To install this Joomla! extension, use the following procedure:
 Configuration Instructions
 ==========================
 
-After installation, configuration can be accomplished through the Joomla!
-Plugin Manager (from the Extensions menu).
+After installation, configuration can be accomplished through the Plugin
+Manager (from the Extensions menu).

mailbox.php

@@ -1,6 +1,6 @@
 <?php
 /**
- * Source file for the Authentication - Mailbox Joomla! plugin
+ * Source file for the Authentication - Mailbox plugin
  *
  * @version		$Id$
  * @package		Auth_Mailbox

mailbox.xml

@@ -8,7 +8,7 @@
 	<copyright>Copyright (C) 2010 Digital Engine Software, LLC. All rights reserved.</copyright>
 	<license>http://www.gnu.org/licenses/gpl-2.0.html GNU/GPL</license>
 	<authorEmail>klocke@digitalenginesoftware.com</authorEmail>
-	<authorUrl>github.com/kevinoid/joomla-auth-mailbox</authorUrl>
+	<authorUrl>github.com/kevinoid/auth-mailbox-joomla</authorUrl>
 	<version>1.0.0</version>
 	<description>PLUGINDESC</description>
 	<files>