MOB-1704

We can handle service errors when we have `returnInstance` option now in MW `Http` class. I changed our model so it always requires the instance of `MWHttpRequest`, therefore we can serve service errors such as "Name needs to be unique" for creating tilesets.
The order isn't so important for a translator but it definitely helps developers keep the i18n file clean. And thanks to taking a closer look at it I found some messages missing in `qqq`. Fixed. Thanks!