fix tests for special regions
translate "Attachments" in Reviewer Tools
use `select_related(related_names)` instead of deprecated `select_related(depth=1)` (bug 1011676)
remove "UI Guidelines" and "Deploying Your App" ecosystem pages (bug 1022831)
remove old Add-on Builder landing page (bug 1022030)
Commit from Mozilla Verbatim by user cesperanc@.: 2074 of 2491 strings translated (0 fuzzy).
allow developers to change manifest URLs for hosted apps and trigger re-reviews (bug 944129)
add Punjbai language (bug 1016125)