Fix bug 21664: change setting of LinksUseTabNames to LinksType, and it has 3 choice: Normal, Use Page Name, Use Page Id. the use page id choice will resolve issue of break link.Added Help URL

git-svn-id: https://dotnetnuke.svn.codeplex.com/svn@71744 142e9c35-602f-4880-9f37-ec48a24daa6a