Toggle location

Created a toggle button after searching to allow users to opt to show their location or not.

Asana task:
https://app.asana.com/0/8548956980512/16035494530316/f
add a scape after
 ```javascript
function($event)
```

Also, use the following style for the if else blocks in terms of whitespace and styling
```javascript
if ($scope.userLocation == null && !$scope.userLocationOn) {
  ...
} else {
  ...
}
```
Notice no space after the `!` 
Add an empty line after the end of the function.