Memory leaks

[RafaelPalomar]

Output for reference:

vtkDebugLeaks has detected LEAKS!
Class "CellMap" has 1 instance still around.
Class "vtkEmptyCell" has 1 instance still around.
Class "vtkAlgorithmOutput" has 1 instance still around.
Class "vtkMRMLNodeReference" has 1 instance still around.
Class "vtkObservation" has 1 instance still around.
Class "9vtkBufferIfE" has 2 instances still around.
Class "9vtkBufferIdE" has 1 instance still around.
Class "vtkTypeInt64Array" has 8 instances still around.
Class "vtkInformationExecutivePortVectorValue" has 1 instance still around.
Class "vtkObserverManager" has 1 instance still around.
Class "vtkInformationExecutivePortValue" has 1 instance still around.
Class "vtkInformationIterator" has 1 instance still around.
Class "vtkMRMLModelNode" has 1 instance still around.
Class "vtkEventBroker" has 1 instance still around.
Class "vtkInformationStringValue" has 1 instance still around.
Class "vtkInformationDoubleVectorValue" has 3 instances still around.
Class "vtkCellArray" has 4 instances still around.
Class "vtkPolyData" has 1 instance still around.
Class "vtkTimerLog" has 1 instance still around.
Class "vtkInformationVector" has 4 instances still around.
Class "9vtkBufferImE" has 1 instance still around.
Class "vtkFloatArray" has 2 instances still around.
Class "9vtkBufferIiE" has 5 instances still around.
Class "vtkCommand or subclass" has 7 instances still around.
Class "vtkIntArray" has 5 instances still around.
Class "vtkIdList" has 6 instances still around.
Class "vtkInformation" has 14 instances still around.
Class "vtkDoubleArray" has 1 instance still around.
Class "vtkIdTypeArray" has 4 instances still around.
Class "vtkCollection" has 2 instances still around.
Class "vtkUnsignedLongArray" has 1 instance still around.
Class "vtkCellData" has 1 instance still around.
Class "vtkFieldData" has 1 instance still around.
Class "vtkPointData" has 1 instance still around.
Class "vtkPoints" has 2 instances still around.
Class "vtkStreamingDemandDrivenPipeline" has 1 instance still around.
Class "vtkTrivialProducer" has 1 instance still around.
Class "vtkInformationIntegerValue" has 25 instances still around.
Class "vtkTagTable" has 1 instance still around.
Class "9vtkBufferIxE" has 12 instances still around.

`