WPF samples crash if folder name contains non-ascii characters

[AntonyMak]

Environment: Windows 7

Steps to reproduce:

1. Git checkout the latest urho-samples (Currently b72d055)
2. Build the urho-samples/FeatureSamples/FeatureSamples.sln using Visual Studio 2015
3. Run the Urho.Samples.WPF
4. Everything is working fine
5. Close the Visual Studio
6. Rename the urho-samples folder to urho-samplesÆ
7. Re-build the urho-samplesÆ/FeatureSamples/FeatureSamples.sln using Visual Studio 2015
8. Run the Urho.Samples.WPF
9. The WPF application crashes with the given error dialog

Please let me know how to set the assets path properly so that this crash could be avoided.

Thanks!