changed unconditional 4-second sleep while waiting for result to many short sleeps with break when done. This reduced the project build time from 8 minutes to 6.5 minutes on my laptop.

git-svn-id: https://svn.apache.org/repos/asf/logging/log4j/log4j2/trunk@1595444 13f79535-47bb-0310-9956-ffa450edef68
reduce sleep time to speed up project build time (by about 10 seconds)

git-svn-id: https://svn.apache.org/repos/asf/logging/log4j/log4j2/trunk@1595448 13f79535-47bb-0310-9956-ffa450edef68