Requests for comment/ChangesList formatting

notes and ideas.....
 * ChangeLine (interface)
 * EnhancedChangesLine
 * OldChangeLine
 * EnhancedChangesLine
 * EnhancedChangesBlockGroupLine
 * ChangeLineFormatter (interface)
 * OldChangeLineFormatter
 * EnhancedChangesBlockGroupLineFormatter
 * EnhancedChangesBlockGroup
 * has EnhancedChangeBlockGroupLines