Message after timeout or misconfiguration is not user friendly

[jnweiger]

With 1.2.0-rc.1 we get a nice error message, when the virus scanner cannot be reached. (thanks to #518 )

When the virus scanner is still connected, but no response appears on the socket for ca 100 seconds, then the following message appears (and the upload fails)

This is a followup of #429

[jnweiger]

Also, when the exact name of the virus cannot be detected e.g. due to a misconfigured ID field:

then the error message has broken English

---

This also affects the German translation:

(Interesting that the German translation survived the deleted -> denied change of #514)