Support loading of clinical sample data in Oracle

Only clinical data is supported now, but the path is laid for other
types.

Also added support for private studies.

vars file will have to be changed. See vars.sample.
Remove/ignore s/ora/kettle-home/kettle.properties
Add script to show job audit and errors

Invoke with:

    make -C samples/{oracle,postgres} showdblog
Merge branch oracle_kettle into master