Simplify hex conversion by using Character.digit() method.
This also supports lower case hex, and rejects invalid hex digits and eliminates the table data.
Update the test cases.

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/fileupload/trunk@1458499 13f79535-47bb-0310-9956-ffa450edef68
2 files changed