add webapp-strip-content
remove content from index.html
remove l10n.js
replace - with _ in l10n-ids
use l20n.js
update l10n-id
no inline
switch panel translation API
switch airplane_mode to l20n
switch battery.js to l20n
switch security_privacy to l20n
switch settings.js to l20n
switch storage to l20n
switch wifi.js to l20n
update utils+connectivity