Re-enable Python MLlib tests (require Python 2.7 and NumPy 1.7+)
Complain if Python and NumPy versions are too old for MLlib
Expose method and class - so that we can use it from user code (particularly since checkpoint directory is autogenerated now
Address review comments
Use method, not variable
Address review comment
Correct L2 regularized weight update with canonical form
Merge pull request #462 from mateiz/conf-file-fix

Remove Typesafe Config usage and conf files to fix nested property names

With Typesafe Config we had the subtle problem of no longer allowing
nested property names, which are used for a few of our properties:
http://apache-spark-developers-list.1001551.n3.nabble.com/Config-properties-broken-in-master-td208.html

This PR is for branch 0.9 but should be added into master too.
(cherry picked from commit 34e911ce9a9f91f3259189861779032069257852)

Signed-off-by: Patrick Wendell <pwendell@gmail.com>
Merge pull request #426 from mateiz/py-ml-tests

Re-enable Python MLlib tests (require Python 2.7 and NumPy 1.7+)

We disabled these earlier because Jenkins didn't have these versions.
Merge pull request #437 from mridulm/master

Minor api usability changes

- Expose checkpoint directory - since it is autogenerated now
- null check for jars
- Expose SparkHadoopUtil : so that configuration creation is abstracted even from user code to avoid duplication of functionality already in spark.
Merge pull request #459 from srowen/UpdaterL2Regularization

Correct L2 regularized weight update with canonical form

Per thread on the user@ mailing list, and comments from Ameet, I believe the weight update for L2 regularization needs to be corrected. See http://mail-archives.apache.org/mod_mbox/spark-user/201401.mbox/%3CCAH3_EVMetuQuhj3__NdUniDLc4P-FMmmrmxw9TS14or8nT4BNQ%40mail.gmail.com%3E