Extension of standard DataRow, adds row level tap events. Also there're
onSecondaryTap and onSecondaryTapDown which are not available in DataCells and
which can be useful in Desktop settings when a reaction to the right click is required.
In-place replacement of standard DataTable widget, mimics it API.
Has the header row always fixed and core of the table (with data rows)
scrollable and stretching to max width/height of it's container.
By using DataColumnPlus instead of DataColumn it is possible to control
relative column sizes (setting them to S, M and L). DataRowPlus provides
row-level tap event handlers.