feat: event emit and handle logic

[Michota]

• Create types for most events that occur inside ReactGrid (e.g. ReactGridEvents)
• Create props for ReactGrid component (e.g. onSelectionChange,onFocusChange, and more.)
• Create function to emit events emitEvent()
• Emit events on store updates (for this current moment there are only two events emitted, handled by props mentioned above).