Backwards compatibility of applications properties

[ilayaperumalg]

The application properties of apps need to support the previous stream app starters properties as well.

For instance, JDBC sink app now introduces jdbc.consumer as the prefix while the stream app starters have got just the jdbc as the prefix.

The reason for backwards compatibility is to allow SCDF streams with the previous set of properties but now trying to use the functional app based ones would break the properties merge.