Adjustments due to code-review

- Changed project to .NET 4.0 (we have to support that until the v1.0).
- Changed solution to VS 2010 for consistency with other solutions.
- Removed giant icon and replaced it with two smaller ones (~ 300 KB saved).
- Corrected namespaces.
- Tidied some comments.
- Cleaned up code files.
- Simplified logic.
- Tweaked variable naming.
- In our case, the destructor in ViewModel is not necessary. Stuff will be cleaned up on exit automatically.
- Formatted code files.
Made disposition working (some strange behavior atm)