Allow users to navigate between Accounts

GIVEN I am a user who is associated with more than one Account
THEN A new Navigation element is displayed for the Account
AND WHEN The user clicks that navigation element
THEN A menu is displayed to allow switching between accounts

## Acceptance Criteria

- [ ] IF the user is associated with more than one account, a new clockwork navigation element is displayed
- [ ] If the user clicks the navigation element a flyout menu is displayed
Menu displays

1. A new clockwork icon/indicator for the currently selected Account + the account Name
2. Directly below the Icon/Name display a menu item for 'Default Account / Set Default Account'
- IF the current Account is the Default Account, menu item is Disabled and text "Default Account"
- IF the current Account is NOT the Default Account, menu item is Enabled and text "Set Default Account"
3. [visual divider - horizontal line]
4. (non-clickable text) "Switch Accounts"
5. List of (clickable) Accounts the user can switch to
- Clickable menu item contains small version of clockface account icon + Name of account

Set Default Account:
- [ ] IF the user selects 'Set Default Account' option
1. The currently selected Account is marked as being the Default Account
2. Display a notification alert "You have set {{AccountName}} as your default account during login"

Account List:
- [ ] IF the user selects an account item from the menu
1. Switch to the selected Account
2. Display a notification alert "You have switched to {{AccountName}}"

## Design Prototype
https://www.figma.com/file/vjpHxTfM3IDAroqFiOr6mq/Navigation-Switch-Account-Mar-2021?node-id=3%3A96

### Design Epic
https://app.zenhub.com/workspaces/teamdesign-5f7e450d26b3010018884d96/issues/influxdata/design-resources/30

### Team
Platform Engineering - @aanthony1243 to assign
App Engineering Lead - @alejom99
Product - @russorat (inform @gunnaraasen )
Design - @corriganjohn