Mweb 965

Do not merge
Check if it works because it didn't when I tried to use the same approach in `poi_category.crud.js`, `poi.crud.js` and `map.crud.js`. If it doesn't work and the errors is always `undefined` go with the other approach:
```js
dbCon
   .getConnection(dbCon.connType.all)
   .then(/*...*/)
   .then(/*...*/)
   /*...*/
   .then(/*...*/)
   .fail(/*...*/)
```
If any of the steps fails/throws an error it will stop executing and just go to `fail()`.