Updated desktop media modals

New photo viewer with preloads
New video modal
New document modal
Fixed add user from shared contact
Fixed contact attach
Added mobile-friendly photo/video viewer

Closes #479
Improved FxOS downloads
Bump to 0.3.6
Fixed soundcloud regex

Closes #574
Added Dutch localization from Transifex
Updated translations
Fixed locales
Added Portuguese (Brasil)
Synchronize translations with Transifex
Upgrade to 20th layer
Fixed mobile mozilla field
Improved desktop photo viewer

Fixed delete left chat
Correct autonym of Dutch language

"Dutch" to "Nederlands"
https://en.wikipedia.org/wiki/Dutch_language
Merge pull request #590 from robin0van0der0v/patch-1

Correct autonym of Dutch language
Fixed group participant w/o phone
Improved desktop photo viewer
Supported 2-letter hashtags