Added missing RemoveAccent function

sluggenerator.cs

/// <summary>
/// Generates a permalink slug for passed string
/// </summary>
/// <param name="phrase"></param>
/// <returns>clean slug string (ex. "some-cool-topic")</returns>
public static string GenerateSlug(this string phrase)
{
    var s = phrase.RemoveAccent().ToLower();
    s = Regex.Replace(s, @"[^a-z0-9\s-]", "");                      // remove invalid characters
    s = Regex.Replace(s, @"\s+", " ").Trim();                       // single space
    s = s.Substring(0, s.Length <= 45 ? s.Length : 45).Trim();      // cut and trim
    s = Regex.Replace(s, @"\s", "-");                               // insert hyphens
    return s.ToLower();
}

public static string RemoveAccent(this string txt)
{
    byte[] bytes = System.Text.Encoding.GetEncoding("Cyrillic").GetBytes(txt);
    return System.Text.Encoding.ASCII.GetString(bytes);
}