Another tweak to the formal definition.

[ikiwiki] / doc / todo / redirect_automatically_after_rename.mdwn

In some wikis, (e.g. Mediawiki) after [[renaming|plugins/rename]] 
a page, the old page still exist but only redirect to the
new page.  This is convenient since external sites may
have links pointing to the old url.  

If [[plugins/meta]] plugin is enabled, users can manually edit the
page, and put in '\[[!meta redir=newpage]]', but this is
not very convenient.