dependencies updated

Merge branch 'devel' of https://github.com/tinode/chat into devel

Unread counters: increment only on msg event.

Add sound to aps payload.

Merge pull request tinode#790 from Babkal/patch-1

Update translations.md

Merge branch 'devel'

Merge pull request tinode#767 from shmutalov/patch-5

Typos

typo null -> nil

fix for tinode#761

updated a couple of todos