ctrl-d as input to jshell

[Brian Goetz]

I notice when I exit jshell with ctrl-d (tip build of jdk/jdk) I get an 
exception trace:

Exception in thread "main" jdk.internal.org.jline.reader.EndOfFileException
         at 
jdk.internal.le/jdk.internal.org.jline.reader.impl.LineReaderImpl.readLine(LineReaderImpl.java:564)
         at 
jdk.internal.le/jdk.internal.org.jline.reader.impl.LineReaderImpl.readLine(LineReaderImpl.java:404)
         at 
jdk.jshell/jdk.internal.jshell.tool.ConsoleIOContext.readLine(ConsoleIOContext.java:200)
         at 
jdk.jshell/jdk.internal.jshell.tool.JShellTool.getInput(JShellTool.java:1238)
         at 
jdk.jshell/jdk.internal.jshell.tool.JShellTool.run(JShellTool.java:1174)
         at 
jdk.jshell/jdk.internal.jshell.tool.JShellTool.start(JShellTool.java:975)
         at 
jdk.jshell/jdk.internal.jshell.tool.JShellToolBuilder.start(JShellToolBuilder.java:254)
         at 
jdk.jshell/jdk.internal.jshell.tool.JShellToolProvider.main(JShellToolProvider.java:120)


instead of exiting silently.  (I thought I recall this working quietly 
before, but I could be mistaken.)  In any case, we should probably catch 
EOFE and just exit silently.