Fix #1096: double message in es_AR.po translation.
(grafted from 5c5a1109f1e38fc2aa7a97bc4a9e93189b5834b4)

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extra : source : 5c5a1109f1e38fc2aa7a97bc4a9e93189b5834b4
Merge pull request #31 from ehuelsmann/1.4

Fix #1096: double message in es_AR.po translation.