[PodVersion] Rewrite to use the Commit#pushed attribute.
[PodVersion] Rewrite to use the Commit#pushed attribute.

We do not care about performance at this stage.

billinghamj/trunk.cocoapods.org,CocoaPods/trunk.cocoapods.org,k0nserv/trunk.cocoapods.org,Shawn-WangDapeng/trunk.cocoapods.org,CocoaPods/trunk.cocoapods.org,k0nserv/trunk.cocoapods.org,k0nserv/trunk.cocoapods.org,billinghamj/trunk.cocoapods.org,Shawn-WangDapeng/trunk.cocoapods.org