[SPARK-20601][ML] Python API for Constrained Logistic Regression

[yanboliang]

What changes were proposed in this pull request?

Python API for Constrained Logistic Regression based on #17922 , thanks for the original contribution from @zero323 .

How was this patch tested?

Unit tests.

[SparkQA]

Test build #80019 has finished for PR 18759 at commit 9ea5238.

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

[SparkQA]

Test build #80024 has finished for PR 18759 at commit 54759c4.

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

[WeichenXu123]

LGTM.

[yanboliang]

Merged into master, thanks for reviewing.

[BryanCutler]

@yanboliang , I'm not sure why but this PR did not make it onto the JIRA. I've noticed it has happened a couple times elsewhere too, maybe some script is broken? Just fyi, if you want to add a link manually.

[yanboliang]

@BryanCutler I linked this PR to the JIRA manually. Thanks for remind.

[zero323]

Thanks @yanboliang