Reorganized the PrefetchQueryPlanner so that it returns builders instead of actual messages. It is now responsible for updating the txn's information in the DependencyTracker. This is necessary because this planner has all of the parameter information.
Removed the QueryCache from the PartitionExecutor. This was being used to store the results of prefetched queries. We now use the DependencyTracker for everything. #125
Removed a bunch of extra data structures for prefetch queries that we didn't end up actually needing
Merge branch 'anticache' of github.com:apavlo/h-store into anticache

Conflicts:
	tests/frontend/edu/brown/hstore/specexec/TestPrefetchQueryPlanner.java
	tests/frontend/org/voltdb/regressionsuites/TestPrefetchQuerySuite.java
	tests/frontend/org/voltdb/regressionsuites/TestSmallBankSuite.java