Merge branch 'release/0.1.5' into develop
add option for versions to keep with default of 3
bump dfs-datastores dependency to valid 1.3.4
Merge pull request #34 from twitter/feature/keepversions

add option for versions to keep with default of 3
Add mima plugin. In VersionedKeyValSource.scala, add back the old constructor for binary compatibility.
Add mima plugin. In VersionedKeyValSource.scala, add back the old constructor for binary compatibility.

And add deprecated warning.
Add more comments.
Resolve conflicts with origin.
Merge pull request #35 from reconditesea/klin_add_mima

Add mima plugin. In VersionedKeyValSource.scala, add back the old constructor for binary compatibility.
Bumping Version numbers. Fix buiding errors under 2.10.0 by casting Scheme.
Merge branch 'release/0.2.0'