Refactor Presentation Mode code
Merge pull request #3763 from Snuffleupagus/refactor-PresentationMode

Refactor Presentation Mode code
Update ja locale
Update zh-TW locale
Merge pull request #3778 from Haebaru/master

Update ja locale
Merge pull request #3779 from xavier114fch/zh-TW

Update zh-TW locale
Merge branch 'master' of git://github.com/mozilla/pdf.js into thumbnail-jump