Ability to Manage Data for Multiple Sites from one Master Account

If I have five sites with tracking stats and I decide to sell three of them to three different owners, I’d like to be able to transfer each database to the new owner as well.

But while I’m developing the sites and improving their traffic and search engine rankings, I’d like to view and manage all five sites from only one master account.

In order to enable this for Piwik, we will need to do the following:

  1. Create a separate installation and database for each site, call these "Site Accounts".
  2. Insert tracking code for each site that corresponds to each installation.
  3. Create another Piwik account on an independent installation, call it the "Master Account".
  4. From each site account, give permission to allow the Master Account to access their data.
  5. Provide an option to allow the Master Account to have Superuser access to each site account.
  6. When you sell a site, you or the new owner can disable permissions for that site.