Reloads UITableView after dataSource switch

Fixes #2932

(For the record) reason of this crash is:

- `[UITableView new]` creates a new tableView with *one* section, by default.
- Setting a new dataSource doesn't reload the number of rows or sections.
- There are multiple actions that might trigger a "section view reload" (such as setting a footer!), and this is a source for crashes.

*Thank you all!!*

/cc @SergioEstevao + @koke + @aerych