show wifi connectivity error when trying to share when offline

[adamwulf]

when the user taps a disabled share item, if its b/c its offline then show an offline info panel where share options normally would appear.

• [x] if the button usually shows an extra share panel (like cloud kit) show the share panel with the wifi connection problem icon.
• if the button usually 'just works' and then closes the panel, then show the progress circle then the wifi error icon in the button, then animate back to normal button
  • [x] imgur icon
  • [x] facebook icon
  • [x] twitter icon
  • [x] AirPrint icon
  • [x] tencent weibo
  • [x] sina weibo

[heatherwong]

verified in build 0.8.5 iPad Mini iOS 8.0