Create an uninstaller entry for the Squirrel version
Inlcude Squirrel.exe in the test app nuspec file, so we can run the uninstaller in our integration tests

Also rig the .gitignore file to include the .nupkg file, we need to store it in source control
Cleanup after ourselves
Improved the cleanup process for the temporary files we create in the integration tests
Merge pull request #3 from flagbug/uninstall-entry

Create an uninstaller entry for the Squirrel version