[SPARK-7208] [ML] [PYTHON] Added Matrix, SparseMatrix to __all__ list…

… in linalg.py

Added Matrix, SparseMatrix to __all__ list in linalg.py

CC: mengxr

Author: Joseph K. Bradley <joseph@databricks.com>

Closes apache#5759 from jkbradley/SPARK-7208 and squashes the following commits:

deb51a2 [Joseph K. Bradley] Added Matrix, SparseMatrix to __all__ list in linalg.py

python/pyspark/mllib/linalg.py

@@ -39,7 +39,8 @@
     IntegerType, ByteType
 
 
-__all__ = ['Vector', 'DenseVector', 'SparseVector', 'Vectors', 'DenseMatrix', 'Matrices']
+__all__ = ['Vector', 'DenseVector', 'SparseVector', 'Vectors',
+           'Matrix', 'DenseMatrix', 'SparseMatrix', 'Matrices']
 
 
 if sys.version_info[:2] == (2, 7):