public override string ToString()
        {
            var propertyNames = new List<string>();

              propertyNames.AddPropertyIfNotNull( Name, "Name" );
              propertyNames.AddPropertyIfNotNull( Key, "Key" );
              propertyNames.AddPropertyIfNotNull( CsProjPath, "Path" );

              return string.Join( Environment.NewLine, propertyNames );
        }
        public override string ToString()
        {
            var propertyNames = new List<string>();

              propertyNames.Add( Include );
              propertyNames.AddPropertyIfNotNull( HintPath, "HintPath" );
              propertyNames.AddPropertyIfNotNull( Private, "Private" );
              propertyNames.AddPropertyIfNotNull( SpecificVersion, "SpecificVersion" );
              propertyNames.AddPropertyIfNotNull( RequiredTargetFramework, "RequiredTargetFramework" );

              return string.Join( Environment.NewLine, propertyNames );
        }