Improve meta titles and descriptions
"Docs" are increasingly ranking high on organic search (sample below). This issue is intended to improve the trend by enhance the meta title and descriptions on a per page basis.
- Currently, pages in the user guide display a global meta description "A guide for CiviCRM users". Ideally these descriptions are unique per page.
- Currently the page title appears to be formed by concatentating the 'menu item name' with the site title ("CiviCRM User Guide - CiviCRM Documentation"). This can lead to poor results (like https://docs.civicrm.org/user/en/latest/organising-your-data/overview/ which yields a page title of "Overview - CiviCRM User Guide - CiviCRM Documentation"). Ideally there's more control over the page title, and likely we could remove the "CiviCRM Documentation" portion to better use the avaiable space.