demo integrate snow

[weizman]

a simple demo of how minor modifications (PoC only) to sentry can enhance its capabilities to track iframes as well as the top origin:

• app.js
  • line34 - wrap the call to Sentry.init with SNOW to call it with every new iframe in the page (change seems big but in fact the Sentry.init options did not change at all, only the SNOW wrap was added along with the new 2nd arg win)
  • line113 - change exception buttons to throw both in top and in iframe
• bundle.js (diff is very small even though file is big)
  • minor changes to allow Sentry to support changing windows (real modification will probably be more complexed than that)
• index.html
  • create an iframe for demo purposes
  • include SNOW logic in the page