Need ability to "stop" ads if an ad sends "suspend" message

[GoogleCodeExporter]

Given a device with a large amount of screen real-estate and displaying 
multiple ads, if one ad becomes "active" and sends the application a "suspend" 
message, the ORMMA SDK should be able to notify all other ads of this fact and 
those ads should suspend as well.

This means, among other things, that if the ad is running a timer that may 
result in a display change (i.e. automatically going into an expanded state for 
example) this should be explicitly disallowed.

Additionally, when the ad sends the "resume" notification, it should in turn 
notify all other ads and allow them to restart.

Original issue reported on code.google.com by [email protected] on 11 Feb 2011 at 7:05