Update site shows confusing status when outdated

### Step 1: Please describe your environment

* ZeroNet version: 4197
* Operating system: Windows

### Step 2: Describe the problem:

When i am having outdated revision of the Zeronet, the update site (http://127.0.0.1:43110/1uPDaT3uSyWAPdCv1WkMb5hBQjWSNNACf) is showing confusing text that i am up to date. It should say something like:
"Not up to date" or "Outdated Zeronet!"
[UPDATE TO LATEST VERSION]

Open the update site at http://127.0.0.1:43110/1uPDaT3uSyWAPdCv1WkMb5hBQjWSNNACf while running ZeroNet version 4197 on Windows and reproduce the status message. Trace the update site's status display, then verify that an outdated revision is labeled as outdated and offers an update-to-latest-version action.

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