test for correct bytebuffer folding
test fold permutations with various maxOverflow / offsets
don't discard current maxOverflow if offset is high enough
fix issue when offset changes folding maxOverflow
minor optimizations
preserve segment order when pulling from cache
Fix inverted lexicographic topNs
Merge branch 'master' into fix-topn
fix brokeness with dim extraction dim specs
fix bug with previousStop not being respected for inverse lexi topN
Merge pull request #567 from metamx/hyperloglog-bugfixes

Fix edge cases in HLL folding
address code review comments
better handle dim extraction regex cases
fix inverted logic
Merge pull request #568 from metamx/fix-topn

Fix inverted lexicographic topns and topns with dim extraction dimension specs
Merge pull request #566 from metamx/fix-cached-segments-order

preserve segment order when pulling from cache
Merge pull request #565 from metamx/add-hll-test

test for correct HLL bytebuffer folding
fix backwards incompatiable change with broker.balancer config
make all firehoses work with tasks, add a lot more documentation about configuration
document limitspec in groupby, fixes #394