Fix grammar error in e-mail footer (closes #673).

git-svn-id: http://redmine.rubyforge.org/svn/trunk@1150 e93f8b46-1217-0410-a6f0-8f06a7374b81

config/settings.yml

@@ -106,6 +106,6 @@ ui_theme:
   default: ''
 emails_footer:
   default: |-
-    You have received this notification because you have either subscribed to it, or are involved in.
+    You have received this notification because you have either subscribed to it, or are involved in it.
     To change your notification preferences, please click here: http://hostname/my/account