Everything but the histogram fill is done
Merge branch 'master' of https://github.com/g-ramar/cs186proj2

Conflicts:
	simpleDB/bin/src/simpledb/JoinOptimizer.class

	new file:   simpleDB/bin/src/simpledb/JoinOptimizer.class
	new file:   simpleDB/src/JoinOptimizer.java