Fixed search messages bugs

Fixed unread count in search - Closes #455
Fixed emoji spritesheet bug

Closes #454
Improved styles
Added notification after auth_key generated

Closes #464
Disabled sourceMaps

Closes #458
Added 2 mobile screenshots

#411
Added mobile screenshots to Readme

#411
Fixed packaged apps monifests

Added filters for FFOS
Fixed name for Chrome
Update README.md

Added maintained locations and FxOS instructions
Update README.md

typo fix