Conflicts:
	core/src/main/scala/spark/DAGScheduler.scala
	core/src/main/scala/spark/SimpleShuffleFetcher.scala
	core/src/main/scala/spark/SparkContext.scala

and made DAGScheduler automatically set SparkEnv.

Added immutable map registration in kryo serializer

Made improvements to takeSample. Also changed SparkLocalKMeans to SparkKMeans

I've fixed the bugs detailed in the diff. One of the bugs was already
fixed on the local file (forgot to commit).

Fixes #105.

(you can no longer iterate over a Source multiple times).

Math.min takes 2 args, not 1. This was not committed earlier for some
reason

merge results into rather than requiring a new object allocation
for each element merged. Fixes #95.

takeSamples method takes a specified number of samples from the RDD and
outputs it in an array.