Updates for Sym 2.3 & other

- updated for Sym 2.3. It worked already but removed unnecessary code, renamed deprecated methods etc
- added possibility to store arrays in Session. It is documented in the event.
- adjusted & simplified the Datasource output to meet array's requirement.
- removed the values from param pool since the more complex XML output won't fit the Params environment (nested arrays aren't rendered in Param pool)

Cheers!