Fix issues with detailMode state
Refactor converters a bit
Adjust terminology
Handle NPE
Adjust display of metadata in MergeCell
Simplify MergeCell and DiffCell
Increase scroll increment

Reported by Yu Tang
Fix Done button not enabled in list view after manual selections

Reported by Yu Tang
Retain selections when switching view modes in MergeWindow

Reported by Yu Tang
Make threshold for defaulting to list view settable by outside callers

Requested by cienislaw
Ensure done button is enabled after view switch in MergeWindow