Add ability to request access to restricted page

Apologies if this isn't the correct project, but here goes: 

Building from Post 13782 in the XWiki forum, this is a request for a feature/application to automate access requests for restricted pages. 

This is a feature that is available in Confluence and one that is very useful for managing access with larger user bases. For our case, we use a wiki for documentation from committees and working groups. New users join these groups often and find themselves not having access to specific pages. In Confluence, there is an option to 'request access' when users are lacking permissions to view a page. This is similar to options for accessing docs in Google and Microsoft. Selecting the 'request access' button sends an email to the platform admins, who can review the request and grant access.

See attached for the email admins receive in Confluence. 

Benefits of having a 'request access' feature:

• Streamlines permissions management
• Easier process for users and admin
• Admin receive an automatic email and can easily see which page/user is requesting access
• Improves user experience; instead of user having to email an admin and manually request access to a page

Some suggestions of how this could work in XWiki: 

• Add 'Request access' button to error message for restricted pages
• Incorporate pieces of existing applications
  • Invitation Application (particularly for mail sending component)
  • Message Stream Application (this would send the notifications within the wiki - emails are preferred over notifications in the wiki)
• Emails to admin should display user name, requested right (view, edit, comment, admin?), and link to the page in question to resolve the request

Thanks!