CC-3001: Preferences->"Submit" button renamed to "Save", and should be at the top and the bottom of the screen

Changed all other buttons that says "Submit" to "Save.
Also added some CSS stuff so that the "Save" button at the top of Preference page
have some space between itself and the form below.

airtime_mvc/application/forms/AddUser.php

@@ -81,7 +81,7 @@ class Application_Form_AddUser extends Zend_Form
         $submit = new Zend_Form_Element_Submit('submit');
         $submit->setAttrib('class', 'ui-button ui-state-default right-floated');
         $submit->setIgnore(true);
-        $submit->setLabel('Submit');
+        $submit->setLabel('Save');
         $this->addElement($submit);
     }