Client Access - User management refinements and impersonate user functionality

The ability for Equinox users to 'Impersonate' a client access account has been added. This means if you are setting up a client access account, you can easily switch into the client access account to simulate their view before providing access. This helps you ensure that the account permissions and settings are set up correctly before providing the client with the access details. We have also tidied and simplified the user settings pages.