Organize strings in .properties files

[luixxiul]

#3947 (comment)

Some strings are duping, eg: app.properties#L188 and autofill.properties#L11. We will need to organize them to avoid confusion.

There is a lot of other duplicates too.

[bbondy]

I asked you to post an issue for this, but you already did, thanks :)

[PercussiveElbow]

Hey, interested in trying this. Is there a certain manner the strings should be organised in? :)

[bsclifton]

Reopening after reverting with ab60908