[bug 924655]  Add a facebook field on the user profile for MDN

Fixed the errors
fix block in installation debug section
Add an arrow to main nav items to just show dropdown
Wire up URLs for page deletion, restoration and purgation.
 Fix iPad/WebKit overflow on zone landing pages
Fix bottom margin issue on iPad
Better center alignment of homepage icons with RTL
Fix reverse column 1% offset within wiki article pages
Exclude redirect pages from l10n dashboard
fix and add tests
Additional instructions for manual installation
Merge pull request #1493 from nhenezi/additional-instructions

Additional instructions for manual installation
Merge pull request #1483 from sayanchowdhury/readme-fix

fix block in installation debug section
Merge pull request #1485 from darkwing/redesign-mobile-submenus

Add an arrow to main nav items to just show dropdown
Merge pull request #1487 from darkwing/redesign-main-overflow

 Fix iPad/WebKit overflow on zone landing pages
Merge pull request #1488 from darkwing/redesign-mobile-wiki-bottom

Fix bottom margin issue on iPad
Merge pull request #1489 from darkwing/homepage-icons-rtl

Better center alignment of homepage icons with RTL
Merge pull request #1491 from darkwing/reverse-column-offset

Fix reverse column 1% offset within wiki article pages
Merge pull request #1486 from ubernostrum/deletion-urls

Wire up URLs for page deletion, restoration and purgation.
Merge pull request #1482 from groovecoder/profile-facebook-field-924655

[bug 924655]  Add a facebook field on the user profile for MDN