Fix static data volume mount and add global hover-to-translate mode

Dockerfile

@@ -4,7 +4,7 @@ WORKDIR /app
 
 ENV NODE_ENV=production
 ENV PORT=80
-ENV DATA_DIR=/app/data
+ENV DATA_DIR=/app/store
 
 COPY package*.json ./
 RUN npm install --omit=dev
@@ -13,7 +13,7 @@ COPY index.html styles.css app.js ./
 COPY data/ ./data/
 COPY server/ ./server/
 
-RUN mkdir -p /app/data
+RUN mkdir -p /app/store
 
 EXPOSE 80