COMP: Missing required base class API component

The GetNumberOfFixedParameters is required to be
overriden from the base class. Other similar
interface were previously implemented, so this
should be implmented to provide consistent
API components.

Modules/Core/Transform/include/itkMultiTransform.h:263:34:
error: 'GetNumberOfFixedParameters' marked 'override' but does not
override any member functions
  virtual NumberOfParametersType GetNumberOfFixedParameters() const ITK_OVERRIDE;

Change-Id: I7f2565cd41c87c6d683f90572abfa7de046aa3ad
Merge topic 'FixMissingBaseClassAPIElement'

1238f63e COMP: Missing required base class API component