[SPARK-2051]In yarn.ClientBase spark.yarn.dist.* do not work

  files = Option(files).getOrElse(sparkConf.getOption("spark.yarn.dist.files").
    map(p => Utils.resolveURIs(p)).orNull)
As you say the code should look like this
```scala
  files = Option(files).getOrElse(sparkConf.getOption("spark.yarn.dist.files").
    map(p => Utils.resolveURIs(p)).orNull)

  archives = Option(archives).getOrElse(sparkConf.getOption("spark.yarn.dist.archives").
    map(p => Utils.resolveURIs(p)).orNull)
``` 
`spark.yarn.dist.*`  and `--archives/--files` behavior is different, this is a bit strange.