[SPARK-10276][MLlib][PySpark] Add @since annotation to pyspark.mllib.recommendation

[yu-iskw]

No description provided.

[SparkQA]

Test build #42232 has finished for PR 8677 at commit 3b3e1e1.

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

[SparkQA]

Test build #42254 has finished for PR 8677 at commit 42916c5.

• This patch passes all tests.
• This patch merges cleanly.
• This patch adds the following public classes (experimental):
  • case class Instance(w: Double, a: Vector, b: Double)
  • class WeibullGenerator(
  • class IndexToString(JavaTransformer, HasInputCol, HasOutputCol):

[noel-smith]

Think this was only added in 1.4.0

[noel-smith]

LGTM apart from the one minor issue above & changing addedversion to versionadded below.

[noel-smith]

Should be .. versionadded::

[SparkQA]

Test build #42530 has finished for PR 8677 at commit df31327.

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

[mengxr]

Merged into master. Thanks!