[SPARK-7744] [DOCS] [MLLIB] Distributed matrix" section in MLlib "Data Types" documentation should be reordered.
[SPARK-7744] [DOCS] [MLLIB] Distributed matrix" section in MLlib "Data Types" documentation should be reordered.

The documentation for BlockMatrix should come after RowMatrix, IndexedRowMatrix, and CoordinateMatrix, as BlockMatrix references the later three types, and RowMatrix is considered the "basic" distributed matrix.  This will improve comprehensibility of the "Distributed matrix" section, especially for the new reader.

Author: Mike Dusenberry <dusenberrymw@gmail.com>

Closes #6270 from dusenberrymw/Reorder_MLlib_Data_Types_Distributed_matrix_docs and squashes the following commits:

6313bab [Mike Dusenberry] The documentation for BlockMatrix should come after RowMatrix, IndexedRowMatrix, and CoordinateMatrix, as BlockMatrix references the later three types, and RowMatrix is considered the "basic" distributed matrix.  This will improve comprehensibility of the "Distributed matrix" section, especially for the new reader.

(cherry picked from commit 3860520633770cc5719b2cdebe6dc3608798386d)
Signed-off-by: Xiangrui Meng <9616cf314f60cbadfd3d5d51110130ad7923defb@databricks.com>

andrewor14/iolap,andrewor14/iolap,andrewor14/iolap,andrewor14/iolap,andrewor14/iolap,andrewor14/iolap,andrewor14/iolap