/// <summary>
/// Deletes a file or directory from the external source's hard drive
///
/// MMEMory:DELete
/// </summary>
/// <param name="extSource">the EXTSOURCE object</param>
/// <param name="filename">filename to save settings to</param>
/// <param name="msus">mass storage unit specifier aka drive</param>
public void DeleteExtSrcMemFile(IEXTSOURCE extSource, string filename, string msus)
{
extSource.DeleteExtSrcMemFile(filename, msus);
}