[bug 1027286] Gengo translation system status

* adds outstanding orders to Gengo admin page
* adds "last seven days" section to Gengo admin page showing total
  number of orders created and completed
* tweaks the "product" section of the Gengo admin page
* adds GengoJob and GengoOrder admin pages
[bug 1027291] Implement spot Gengo human translation
Change recent() to only show 7 days of journal records
Make completed not require a value
Fix default threshold