[SPARK-9122] [MLLIB] [PySpark] spark.mllib regression support batch predict

[yanboliang]

spark.mllib support batch predict for LinearRegressionModel, RidgeRegressionModel and LassoModel.

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Merged build triggered.

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Merged build started.

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Merged build finished. Test FAILed.

[yanboliang]

Jenkins, test this please.

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Merged build triggered.

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Merged build started.

[SparkQA]

Test build #77 has started for PR 7614 at commit 4e610c0.

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Merged build triggered.

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Merged build started.

[SparkQA]

Test build #38209 has started for PR 7614 at commit 4e610c0.

[SparkQA]

Test build #77 has finished for PR 7614 at commit 4e610c0.

• This patch passes all tests.
• This patch merges cleanly.
• This patch adds the following public classes (experimental):
  • class TrainValidationSplit(override val uid: String) extends Estimator[TrainValidationSplitModel]
  • case class CreateArray(children: Seq[Expression]) extends Expression
  • case class CreateStruct(children: Seq[Expression]) extends Expression
  • case class CreateNamedStruct(children: Seq[Expression]) extends Expression

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Merged build finished. Test PASSed.

[SparkQA]

Test build #38209 has finished for PR 7614 at commit 4e610c0.

• This patch passes all tests.
• This patch merges cleanly.
• This patch adds the following public classes (experimental):
  • class TrainValidationSplit(override val uid: String) extends Estimator[TrainValidationSplitModel]

[AmplabJenkins]

Merged build finished. Test PASSed.

[jkbradley]

LGTM, merging with master.
Thanks!