Remove props to implement subrows

[amanmahajan7]

• Remove SubRow props
  • getSubRowDetails
  • onCellExpand
  • onDeleteSubRow
  • onAddSubRow - this prop was not used
• Update TreeView example and implement subrows without the above props. SubRows implementation felt too complicated and I ended up using a simpler model
• Combine TreeView and TreeViewNoDelete examples
• Tsify CellActions example

Next step is to replace defaultCellContentRenderer with defaultFormatter

[nstepien]

Looks great overall

[nstepien]

It doesn't matter too much for demos, but we should avoid passing new functions on each render to DataGrid.

[amanmahajan7]

I am thinking of using eventBus more aggressively and avoid passing callbacks down. I have a few ideas that we can discuss next week