set_attribute_boolean
  
  Description:
  public void set_attribute_boolean (
string attribute, 
bool attr_value)
  
 
  
    Sets the attribute to contain the given attr_value, if possible.
    Parameters:
    
      
        | this | 
        
           a FileInfo. 
         | 
      
      
        | attribute | 
        
           a file attribute key. 
         | 
      
      
        | attr_value | 
        
           a boolean value. 
         |