Adds meta[rel=alternate hreflang] to tutorials
link instead of meta
More seamless background images for larger displays

- Made the 4 main hero images subtly fade to black
- Make body background colour black to hide background edges
- Slightly adjusted related background styles to avoid !important
declarations where possible
Remove unnecessary empty body rule
Actually adding updated background images

Ooops.
Merge remote-tracking branch 'upstream/master' into background-images
Add Building web apps with Yeoman and Polymer, profile
translation of site UI strings into Korean.
Adding link, generator-webapp mention
upload mo file.
Removing outdated information

The getResponseHeaders() bug has been fixed in all browsers.
update UI String
added text compression article.
updated tutorials.yaml
Merge pull request #641 from jakearchibald/master

Fixing SVG embed
Addressing feedback from Arthur
fix unmatched msgid & msgstr
Merge pull request #627 from addyosmani/master

Fixes #571 - Adds 'Building webapps with Yeoman and Polymer'
Fixes some issues with the article reporting tool
Quick fix to tutorials