RFR 8085882: JShell tool: Completion for primitive types

[ShinyaYoshida]

Hi Jan,
Could you review this?

bugs:
https://bugs.openjdk.java.net/browse/JDK-8085882

webrev:
http://cr.openjdk.java.net/~shinyafox/kulla/8085882/webrev.00/

Regards,
shinyafox(Shinya Yoshida)