Add project short title, set standard site title, project name cleanup

In another move aimed for better consistency across the j.org network, I've reworked the main title displayed in the page header some.  It will now always show as "Joomla! Issue Tracker" with the ability to append to it, used for the tracker pages.  To keep the title from running too long, I've added a `short_title` field for the projects table and use that to display a unique appendix for the trackers.  So now we display "Joomla! Issue Tracker - CMS" instead.

Point 2 with this is cleanup of the project names and aliases, ultimately aimed for a better experience.  "Joomla! CMS 3 Issues" is shortened to just "Joomla! CMS" and its alias shortened the same.