Allow <Status> component's `text` object to contain properties with component/node values

[rnicholus]

...instead of just strings, that way you could do something like this:

const statusText = {
  upload_failed: <span>Failure <img src='red-x.png'/></span>,
  upload_successful: <span>Success! <img src='green-checkbox.png'/></span>,
  ...
}

<Status text={ statusText} />

The above would easily allow images/icons to be part of the status message. Additionally, if you use something like react-intl, this makes it a bit less awkward (IMHO) to provide translatable text:

const statusText = {
  upload_failed: <FormattedMessage id='Uploader.failed' />,
  ...
}