stop leaking astyanax internals out of the reader
clean up updating shard state
remove code duplication in getColumns
update catch to match what is thrown
go back to not batching shard state reads
create a new ShardState class for tracking Shard State
use ShardState objects for reads and writes
Merge pull request #199 from fourk/cleanup_reader

RFR Reader Cleanup Part 2
replace Util.formatStateColumnName
move ShardState-specific code out of Util into ShardState
rename ShardState to SlotState
move string-representation of slotstate to the serializer
Modify set rollups to track individual items seen instead of counters.

This is done by hashing each object as it observed, and storing the hashes.  hashes are then merged on rollup.

This puts SetRollup in the same class as TimerRollup in that full-resolution stores rollup objects rather than primitives.
Update README.md
introduce a 5ms gap into the time between when a thread starts and it starts running its runnable. This will make the test work the way it is expected.
Merge pull request #204 from gdusbabek/slow_batch_read_test

Fix testBatchGet() failures
Merge branch 'master' into set_rollups_v2
use getHashes() instead of accessing hash directly.
update changes
Merge pull request #203 from gdusbabek/set_rollups_v2

Set rollups v2 - track individual items across rollups (up to 24h)