[SPARK-7888] Be able to disable intercept in linear regression in ml package

[holdenk]

No description provided.

[SparkQA]

Test build #35418 has finished for PR 6927 at commit 3bb9ee1.

• This patch fails Scala style tests.
• This patch merges cleanly.
• This patch adds no public classes.

[SparkQA]

Test build #35419 has finished for PR 6927 at commit 319bd3f.

• This patch fails Scala style tests.
• This patch merges cleanly.
• This patch adds no public classes.

[SparkQA]

Test build #35421 has finished for PR 6927 at commit f34971c.

• This patch passes all tests.
• This patch merges cleanly.
• This patch adds no public classes.

[dbtsai]

remove extra line.

[dbtsai]

LGTM except minor issues.

[dbtsai]

new line

[dbtsai]

Too long. Or just import shared._

[SparkQA]

Test build #35526 has finished for PR 6927 at commit ae5baa8.

• This patch fails MiMa tests.
• This patch merges cleanly.
• This patch adds no public classes.

[dbtsai]

remove the extra line.

[dbtsai]

Although LeastSquaresAggregator and LeastSquaresCostFun are private, MiMa is not happy about the changes.

[error]  * method this(org.apache.spark.mllib.linalg.Vector,Double,Double,Array[Double],Array[Double])Unit in class org.apache.spark.ml.regression.LeastSquaresAggregator does not have a correspondent in new version
[error]    filter with: ProblemFilters.exclude[MissingMethodProblem]("org.apache.spark.ml.regression.LeastSquaresAggregator.this")
[error]  * method this(org.apache.spark.rdd.RDD,Double,Double,Array[Double],Array[Double],Double)Unit in class org.apache.spark.ml.regression.LeastSquaresCostFun does not have a correspondent in new version
[error]    filter with: ProblemFilters.exclude[MissingMethodProblem]("org.apache.spark.ml.regression.LeastSquaresCostFun.this")

Please exclude them. Thanks.

[SparkQA]

Test build #35530 has finished for PR 6927 at commit 4016fac.

• This patch fails MiMa tests.
• This patch merges cleanly.
• This patch adds no public classes.

[SparkQA]

Test build #35534 has finished for PR 6927 at commit 0ad384c.

• This patch passes all tests.
• This patch merges cleanly.
• This patch adds no public classes.

[dbtsai]

Thanks. Merged into master.