Fix some straggling JDK6 issues.
Merge pull request #29 from rankinc/tidy-up-jdk6

Fix some straggling JDK6 issues.  Reviewed.
Merge branch 'master' into cloned-properties
Fix references to XA states in comments, and remove unused import.
More final variables and @Override annotations.
Add generic types to List and Iterator.
Merge branch 'master' into cloned-properties