Yaml: Flatten list objects (Idea)

We could flatten the configuraiton of list elements.
E.g.
```yaml
properties:
  - property:
      name: driverClassName
      value: org.h2.Driver
  - property:
      name: url
      value: jdbc:h2:./membranedb;AUTO_SERVER=TRUE
``` 

could look like this:
```yaml
properties:
  - name: driverClassName
    value: org.h2.Driver
  - name: url
    value: jdbc:h2:./membranedb;AUTO_SERVER=TRUE
``` 

