FIX: @Thread(0) annotation cause incorrect microbenchmark generation

[Sergey Kuksenko]

Hi All,

BUG:
JMH annotation processor in case of @Thread(0) annotation generates code 
which fails with division by zero.

Fix suggested:
http://cr.openjdk.java.net/~skuksenko/jmh/zerothreads-bug/webrev.00/

-- 
Best regards,
Sergey Kuksenko