Javadoc modifications, remove unnecessary cast.
Escape html in javadoc to make EOGenerator template changes able to be simply copy-pasted. The previously displayed class Javadoc would create errors if copy-pasted. Also improved clarity of many of the method Javadoc comments. Removed an unnecessary cast.
Merge pull request #568 from nekesto/ERXCopyable_Javadoc_Fix

ERXCopyable Javadoc modifications, remove unnecessary cast.