armstrong-numbers: Regenerate exercise README to pick up new content from insert
armstrong-numbers: Regenerate exercise README to pick up new content from insert

GKotfis/csharp,exercism/xcsharp,robkeim/xcsharp,ErikSchierboom/xcsharp,ErikSchierboom/xcsharp,GKotfis/csharp,exercism/xcsharp,robkeim/xcsharp