load balancing coalescer
Bug, should compute slack wrt parent partition size, not number of bins
Large scale load and locality tests for the coalesced partitions added
added goals inline as comment
word wrap before 100 chars per line
Renamed split to partition
Fix bug in tests
made preferredLocation a val of the surrounding case class
use count rather than foreach
space removed
several of Reynold's suggestions implemented
Made a function object that returns the coalesced groups
fixed matei's comments
Added error messages to the tests to make failed tests less cryptic
added one test that will test a future functionality
Coalescer now uses current preferred locations for derived RDDs. Made run() in DAGScheduler thread safe and added a method to be able to ask it for preferred locations. Added a similar method that wraps the former inside SparkContext.
comment in the test to make it more understandable
making CoalescedRDDPartition public
fixed Matei's comments
Fixed almost all of Matei's feedback