feat: 🎸 Update hotkeys and user preferences modal (#1135)

* feat: 🎸 Update hotkeys and user preferences modal

This feature fix incompatibility with existent hotkeys component and
adds user preferences modal back

Closes: #923

* Update preferences structure in store

* Hide window level section of user preferences

* Update modal to reflect current hotkey value

* Clone object with hotkeys before passing to manager

* CR Update: Extract hotkeys manager format code to manager

* Fix broken cypress test

* Use new modal provider

* Rename hotkeyDefinitions in hotkeyspreferences and use array as representation

* Update study test and remove unused styles

platform/viewer/cypress/integration/common/OHIFStudyViewer.spec.js

@@ -267,8 +267,12 @@ describe('OHIF Study Viewer Page', function() {
   });
 
   it('opens About modal and verify the displayed information', function() {
-    cy.get('[data-cy="options-menu"]').click();
-    cy.get('[data-cy="about-item-menu"]').click();
+    cy.get('[data-cy="options-menu"]')
+      .first()
+      .click();
+    cy.get('[data-cy="about-item-menu"]')
+      .first()
+      .click();
     cy.get('.modal-content')
       .as('aboutOverlay')
       .should('be.visible');