Continuous progress image enhancement

Nic, here is the pull request with the changes. Please check the two .csproj files as my VS2013 removed the $(MSBuildBinPath) and added $(MSBuildExtensionsPath). Not sure if this affects anyones project.


![projectchanges](https://cloud.githubusercontent.com/assets/1189224/2690317/33f6b3c4-c33c-11e3-8353-a948c3714993.png)

![showprogresswithimage](https://cloud.githubusercontent.com/assets/1189224/2690319/788a9f32-c33c-11e3-8575-904ef04d2ef6.png)