IgniteRDD.keepBinary()

[Valentin Kulichenko]

Folks,

I added the IgniteRDD.keepBinary() method, as described in [1]. Changes are
committed to branch ignite-3215.

Alexey Goncharuk, since you were implementing IgniteRDD, can you please
take a look and check if everything is fine?

[1] https://issues.apache.org/jira/browse/IGNITE-3215

-Val

[Alexey Goncharuk]

​Val,

Looks good to me, can't wait to see it in master :)