Use Bootstrap progress bars in web UI

Minor mllib cleanup

Renamed Classification.scala to ClassificationModel.scala and Regression.scala to RegressionModel.scala

made SimpleUpdater consistent with other updaters

This fixes SPARK-832, an issue where PySpark
would not work when the master and workers used
different SPARK_HOME paths.

This change may potentially break code that relied
on the master's PYTHONPATH being used on workers.
To have custom PYTHONPATH additions used on the
workers, users should set a custom PYTHONPATH in
spark-env.sh rather than setting it in the shell.

Internal cleanup

Remove duplicate loss history in Gradient Descent

Also renamed MasterState to MasterStateResponse and WorkerState to WorkerStateResponse for clarity.

Conflicts:
	core/src/main/scala/spark/ui/jobs/IndexPage.scala

Totals for shuffle data and CPU time

Also some minor style fixes.

cially if it merges an updated upstream into a topic branch.

Fix two small usability issues

Adding SVM and Lasso

Lines shortened to < 100 characters

Classifiers return categorical (Int) values that should be compared
directly

One unfortunate consequence of this fix is that we materialize any
collections that are given to us as generators, but this seems necessary
to get reasonable behavior on small collections. We could add a
batchSize parameter later to bypass auto-computation of batch size if
this becomes a problem (e.g. if users really want to parallelize big
generators nicely)