RFR 8143955: JShell tool (UX): Output structure

[Robert Field]

This is the new feedback definitions.
Besides the configuration commands (embedded in the properties file), 
and a few output fix-ups, this is mostly lots of test changes,

Bug:
     8143955: JShell tool (UX): Output structure
     8143956: JShell tool (UX): default prompts

Webrev:
     http://cr.openjdk.java.net/~rfield/8143955.webrev/

Thanks,
Robert