Fix rhq-28: Addtional configuration elements

- storage-adapter
- server-monitor
- diagnostics

In addition to that:

- updated readme
- improve service lifecycle


well, I think complex attributes are an edge case and not the norm. furthermore the scheduler internals have been build with single attribute references in mind (distinct samples). in general we would like to avoid any automagic conversion of complex attributes into metric samples. the current metric configuration, also not being fully implemented  in the scheduler, allows for accessing complex attributes of type ModelType.OBJECT (like in the heap example), but also ModelType.LIST (i.e. attributeName#0).