Edit component will look like add component with following changes.
1. Instead of "Add Employee" the page heading should read "Edit Employee".
2. Instead of "Save" button at the end of the page, we'll have "Update" button.
3. Add a new input field "Leaving Date". It should be a datepicker control and should follow the same format. It is not a required field.
4. "Joining Date" is required here.
5. The form should pre-populate with all the values of the employee which the user is going to edit.
