Unnecessary casts

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/compress/trunk@1482150 13f79535-47bb-0310-9956-ffa450edef68
Unused imports

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/compress/trunk@1482151 13f79535-47bb-0310-9956-ffa450edef68