RFR: JDK-8193352: SA: Test for the clhsdb 'thread' and 'threads' commands

[Jini George]

Hello,

I would like to request reviews for:
Id: https://bugs.openjdk.java.net/browse/JDK-8193352
Webrev: http://cr.openjdk.java.net/~jgeorge/8193352/webrev.00/index.html

This is a test case for the clhsdb 'thread' and 'threads' commands. This 
also includes a minor fix for the incorrect printing of the text 
'Couldn't find thread -a' when the 'thread -a' command is specified.

Thanks,
Jini.