OptionalchartThe cell content type.
Can be one of the following: 'text', 'checkbox', 'select',
'textInput', 'dateInput', 'dateTimeInput', 'timeInput',
'numberInput', 'sparkline'.
You can also create your own custom renderer by extending the
CellRenderer class and registering it in the
CellRendererTypeRegistry.
Options to control the sparkline renderer content.