Change SVM to use {0,1} labels.
Also add a data validation check to make sure classification labels
are always 0 or 1 and add an appropriate test case.
Fix SVM model and unit test to work with {0,1}.
Also rename validateFuncs to validators.
Specify label format in LogisticRegression.
Adding Linear Regression, and refactoring Ridge Regression.
Centralizing linear data generator and mllib regression tests to use it.
Fixing typos in Java tests, and addressing alignment issues.
Pass SBT_OPTS environment through to sbt_launcher
Center & scale variables in Ridge, Lasso.
Also add a unit test that checks if ridge regression lowers
cross-validation error.
Add an option to turn off data validation, test it.
Also moves addIntercept to have default true to make it similar
to validateData option
Change to use Yarn appropriate directories rather then /tmp or the user specified spark.local.dir
Revert "Merge pull request #841 from rxin/json"

This reverts commit 1fb1b0992838c8cdd57eec45793e67a0490f1a52, reversing
changes made to c69c48947d5102c81a9425cb380d861c3903685c.
Added worker state to the cluster master JSON ui.
Throw exception if the yarn local dirs isn't set
Merge pull request #864 from rxin/json1

Revert json library change
Update docs and remove old reference to --user option
Add ability for user to specify environment variables
fix typos
Merge pull request #859 from ianbuss/sbt_opts

Pass SBT_OPTS environment through to sbt_launcher
Allow for Executors to have different directories then the Spark Master for Yarn
Updated based on review comments.