MF-641: Completed Patient List Modal

[vasharma05]

What does this PR include?

This PR contains the final completion changes to the patient list modal.

[vasharma05]

www_screencapture_com_2021-7-27_13_56.mp4

Correction: screen width -> screen height

@FlorianRappl @jonathandick I have tried to show the modal and the workflow too. @FlorianRappl this video also contains the workflow, which I want you to go through, it will help in solving out the queries you pointed above and can you please suggest me something better, if this workflow doesn't look good to you.

@jonathandick I want you to please check the text shown in the toasts and direct if any changes are required.

[FlorianRappl]

I already suggested something better.

1. Remove the global closeModal.
2. Remove the openModal.
3. Call showModal directly in the AddPastVisitOverflowMenuItem component:

const openModal = React.useCallback(() => {
  const dispose = showModal('add-patient-to-patient-list-modal', {
    close: () => dispose();
  });
}, []);

[vasharma05]

Thanks @FlorianRappl ! I didn't think of using it this way.
Thanks alot!

[FlorianRappl]

LGTM