Using ThreadUtil instead of Thread.

Modify the sample rate of aLRU. Exclude the index memory in eviction threshold for now.
Restore the timestamp build flag. Some test code on the way.
All right. I forgot to turn on the anticache_build.
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What a bug!!! We do not need to scan the specific block when calculating tupleID in LRU.
Replace set to sort in EvictionIterator.
Add the sort to EvictionIterator.
Replace the tuple-based sampling to block-based in anti-cache timestamps.
Add one block to evict to ensure there's someting when evict_num is really low.
Clean up the allocatortracker test.
Little change to #sample-block.
Rollback the block-sample to tuple-sample. Cleanup of codes.
Add more comments.
Merge branch 'master' of https://github.com/malin1993ml/h-store