message: Sparkle: fix auto update dialog language.
diff: <!-- For Sparkle Framework -->
  <key>SUFeedURL</key>
  <string>https://seafile.com/api/client-updates/seafile-client-mac/appcast.xml</string>
  + <key>CFBundleLocalizations</key>
  + <!-- The CFBundleLocalizations would determinte the display language used by sparkle AutoUpdate.app -->
  + <!-- We must list all languages supported by Sparkle here -->
  + <!-- Sparkle would choose one based on current system language -->
  + <!-- See https://github.com/sparkle-project/Sparkle/issues/238#issuecomment-11927292 -->
  + <array>
  + <string>ar</string>
  + <string>ca</string>
  + <string>cs</string>
  + <string>da</string>
  + <string>de</string>
  + <string>el</string>
  + <string>en</string>
  + <string>es</string>
  + <string>fi</string>
  + <string>fr</string>
  + <string>he</string>
  + <string>is</string>
  + <string>it</string>
  + <string>ja</string>
  + <string>ko</string>
  + <string>nb</string>
  + <string>nl</string>
  + <string>pl</string>
  + <string>pt_BR</string>
  + <string>pt_PT</string>
  + <string>ro</string>
  + <string>ru</string>
  + <string>sk</string>
  + <string>sl</string>
  + <string>sv</string>
  + <string>th</string>
  + <string>tr</string>
  + <string>uk</string>
  + <string>zh_CN</string>
  + <string>zh_TW</string>
  + </array>
  </dict>
  </plist>
  