show connectivity state of other profiles

[r10s]

meanwhile, desktop and even iOS show "connectivity" state in the profile switcher, deltalab/arcane chat does that since forever.

time to update also deltachat-android.

• we can backport the deltalab/arcane feature, that show colored dots on the avatars.

• for iOS, we decided to use a subtitle for that and show the state in plain text - the same as what is shown in the main title. advantage of that approach is that it needs zero explanations, where esp. the meaning of the "green" dot on "profiles" is slightly different than the one on "contacts". but maybe we do not need a green dot at all and say also what is not connected or updating? so same as in title?

• desktop use both, text+dots.

but i would be fine with any solution, i would leave that decision up to @adbenitez