App init bugfixes
Added Spanish localization

Fixed unathorized request. Closes #465
Fixed JSON error in Chrome App mode
Fixed app reload for packaged app
Merged documentation for localization
Merge branch 'pr/471'
Update README.md
Fixed default locale problem
Fixed unread after
Fixed mobile prepend history
updated german locale: added new message
Revert "put current locale in consideration for various caches in filters/services"

This reverts commit 37bb69a409e2ed721def80c69e7727572bfdc17d.

Since we moved i18n into the init phase in
f1db5e1c962e458cc5da787cf8c248ebe23294f8 and don't switch locale at
runtime we don't need this anymore
updated i18n guide

reflect changes of f1db5e1c962e458cc5da787cf8c248ebe23294f8