Add manageable doc pages that provide instructions and help per common page

Often, in production clouds, users are not experienced enough with stuff they get via cloud.
So, it would be useful to provide some markers on lots of pages that will refer to "doc" pages,
where operator or cloud admin can define deployment-specific information with text, images and other kinds of files.

Here is requirements from admin point of view:

- add panel "doc pages" to "admin" dashboard.
- make this panel be able to "create", "edit", "view" and "delete" doc pages.
- each doc page should be allowed to be assigned to one specific link.
- doc pages views should be visible for all.
- it should be possible to attach files to doc pages.
- there should be difference in access to "control" dashboard of doc pages (admin) and their views (all users).
- make attached files be stored in swift.

Here is requirements from user point of view:
- assigned doc page should look as marker that refers to specific link with doc pages.
- marker should be located for right from page title
- marker with link to doc page should be distinguishable enough from first sight

Screenshots with example:
1) Index page with doc pages - http://imgur.com/0phPsLI
2) View of "edit" form for doc page - http://imgur.com/gv4aT8y
3) View of doc page itself - http://imgur.com/8paI0Zr