[UIMA-1249] [UIMA-1598] fixes supporting multiple initialize calls on multiple threads. Make fields either final or volatile, per JCIP (Java Concurrency in Practice)

git-svn-id: https://svn.apache.org/repos/asf/uima/uimaj/trunk@1587714 13f79535-47bb-0310-9956-ffa450edef68