Merge pull request #61 from leventov/master

map_index fix; append_array optimization
null-safe udf.collect.CreateWithPrimitive
Merge pull request #63 from leventov/master

null-safe udf.collect.CreateWithPrimitive
Added collect_merge_max (not working)
-added optional second param to hyperloglog udaf for specifying precision (b parameter)
-updated union_hll to match changes to hll
Merge pull request #64 from ap-ensighten/dev/hll.precision.param

Added optional second parameter to hyperloglog to specify the precision (b parameter)
Finished collect_merge_max
Optimized map_key_values
Fixed collect_merge_max bug for strings & timestamps
Removed unused code in udf.collect.AbstractCollectMergeUDAF
Made collect_merge_max more null-safe
Optimized udf.collect.CollectMergeMaxUDAF to produce less temporary boxed primitives
Merge pull request #66 from leventov/master

collect_merge skeleton; collect_merge_max; optimized map_key_values a bit
Fixed klout/brickhouse#68 - deoptimized append_array to always behave correctly
Merge pull request #70 from leventov/master

Fixed klout/brickhouse#68 - deoptimized append_array to always behave correctly
-handle column only has nulls
-add some initial tests for hll
Merge pull request #72 from ap-ensighten/issue-71

-handle column only has nulls
-temporarily disabled hll tests while still debugging issues with them

temporarily addresses #75
Merge pull request #77 from ap-ensighten/bug/issue-75

-temporarily disabled hll tests while still debugging issues with them