expandAll option useExpanded hook

[aleyan]

Hi,

I have a use case where I want all the rows to start out auto expanded. More over, new rows may be added after initial load, and they should be expanded as well. I don't think the right solution is to add every row to initialState.expanded, because more may appear after initialization.

In my fork, I have added a expandAll option to useExpanded hook that forces all rows to auto expand. It requires further work before it is ready to be upstreamed however. Alternatively, I am thinking about adding a "initial expansion state" option that will determine how if any what boolean value any new rows will be placed into expanded object. Is there a desire for either of these options in this project?