If adding to an empty value, set it as an array

If we have an empty field ‘test’ and we specify the sql `SET test += “test”` then we’ll presume it’s going to be an array if it isn’t a number or a decimal.

util/data/data.go

@@ -845,6 +845,8 @@ func (d *Doc) Inc(value interface{}, path ...string) (*Doc, error) {
 			return d.Set(0+inc, path...)
 		case float64:
 			return d.Set(0+inc, path...)
+		default:
+			return d.Set([]interface{}{value}, path...)
 		}
 	case int64:
 		switch inc := value.(type) {