Updated user icon to use default when one isn't specified

## What is this?

This sets a default icon if one doesn't exist for the user.  Per http://www.flickr.com/services/api/misc.buddyicons.html, http://www.flickr.com/images/buddyicon.gif should be used for the icon if the icon server isn't greater than zero.

For this case `user_info["iconfarm"]` was returning `nil` causing `NoMethodError: undefined method '>' for nil:NilClass`.