Merge branch 'release/0.9.0rc1' into develop
Update README.md: Adding artifacts names for scalding-commons and scalding-avro
test approximateUniqueCount
Merge pull request #646 from epishkin/approximateUniqueCount

test approximateUniqueCount
Merge pull request #645 from david206/patch-4

Update README.md: Adding artifacts names:scalding-commons and scalding-avro
Fixup some chill
Remove semigroup on ValuePipe
cleanup adaptive vector serializers
Merge pull request #649 from twitter/scalar-cleanup

Remove semigroup on ValuePipe
fix grammar
Merge pull request #648 from twitter/chill-bump

Fixup some chill
use cascading 2.2.0 final release
Merge pull request #653 from fs111/develop

use cascading 2.2.0 final release
latest set of dependencies to scald
Merge pull request #657 from krishnanraman/develop

latest set of dependencies to scald
Make mocking cofigurable in Test
Add sumByKey
Merge pull request #663 from twitter/transformTest

Make mocking cofigurable in Test
Merge pull request #664 from twitter/sumByKey

Add sumByKey
mark version 0.9.0rc2, not published