Remove scenes (#36)

* Remove scenes from the main menu

* Remove scenes from the profile view

* Remove 'scenes explainer' from onboarding flow

* Remove scene-related modals

* Remove member/membership code

* Remove all scenes-related items from notifications

* Remove scene-related code from posts feed

* Remove scene-related API helpers

* Update tests

__tests__/view/shell/mobile/Menu.test.tsx

@@ -57,14 +57,4 @@ describe('Menu', () => {
     expect(onCloseMock).toHaveBeenCalled()
     expect(mockedNavigationStore.switchTo).toHaveBeenCalledWith(1, true)
   })
-
-  it('presses new scene button', () => {
-    const {getAllByTestId} = render(<Menu {...mockedProps} />)
-
-    const menuItemButton = getAllByTestId('menuItemButton')
-    fireEvent.press(menuItemButton[3])
-
-    expect(onCloseMock).toHaveBeenCalled()
-    expect(mockedShellStore.openModal).toHaveBeenCalled()
-  })
 })