Fix: Word export encoding was said to be latin, but is in fact UTF-8
Dev: by default Word uses local 8-bit encodings (CP-1252 for Europe etc.) but LimeSurvey exports UTF-8 without specifying the encoding in the resulting document. This patch adds a tag setting charset to UTF-8 in the resulting .doc. It also corrects the label of the export option from latin to UTF-8.