Changed one line of the translation to something meningful

[mwd]

The afore used translation was insufficient at best. Actually it did not describe the problem at all.

[kylehuff]

Unfortunately, I cannot accept this pull request as it would cause the other translations within launchpad to be out of sync. All translations for WebPG are managed within launchpad.net; I export the updated PO files from there and merge them into the repository. Instead, I will add this fix via launchpad and it will be corrected in the repo on the next merge.

Thanks for the effort though, I appreciate it greatly. For any other fix this would be the desired method.

(I will leave this pull request open until I have made the required changes via launchpad.net)