Implicit exports instead of explicit ones

[GALCF]

https://github.com/Brainshaker95/simple-form-elements/blob/831454da04612d65705c597cd91e5ece7c791240/src/js/simple-checkbox/simple-checkbox.js#L4

The exports in this file and other files like this one should be implicit, if possible, like so:

export * from 'src/first_module';
export * from 'src/other_module';

[pfaffenrodt]

@GALCF eslint says it should provide an default export.

I would prefer named exports. So refactoring/renaming can be done with your Editor easily.
Something like this.

export {
    simple-checkbox as default
};