8171981: JShell: Fails compilation: new Object().getClass().getSuperclass()
Reviewed-by: mcimadamore

8154485: JShell: infrastructure for multi-Snippet class wrappers
Reviewed-by: jlahoda

8131027: JShell API/tool: suggest imports for a class
Summary: Adding two new actions to JShell: add imports and create variable.
Reviewed-by: rfield

8145239: JShell: throws AssertionError when replace classes with some methods which depends on these classes
Reviewed-by: rfield
Contributed-by: bitterfoxc@gmail.com

8134254: JShell API/tool: REPL for Java into JDK9
Summary: Adding the implementation of the jshell (read-eval-print-loop) tool.
Reviewed-by: briangoetz, mcimadamore, psandoz, forax
Contributed-by: robert.field@oracle.com, bitterfoxc@gmail.com, jan.lahoda@oracle.com