Use -XX:MaxGCPauseMillis=50 in conjunction with Thread.sleep(51) to wait 51ms
after a GC call, instead of waiting 10s.

http://docs.oracle.com/javase/1.5.0/docs/guide/vm/gc-ergonomics.html

$ make JunitTest_juh

Change-Id: Id2cdada0e493fd450aab5dbec164502e0173857f
Reviewed-on: https://gerrit.libreoffice.org/11593Reviewed-by: David Ostrovsky <David.Ostrovsky@gmx.de>
Tested-by: David Ostrovsky <David.Ostrovsky@gmx.de>