Update RELEASE_NOTES.txt for release.
[maven-release-plugin] prepare release kiji-express-0.8.1
[maven-release-plugin] prepare for next development iteration
EXP-172. Allow users to read SpecificRecords in KijiExpress

issue: https://jira.kiji.org/browse/EXP-172
review: https://review.kiji.org/r/987
POM-9. Upgrade to Avro 1.7.5

issue: https://jira.kiji.org/browse/POM-9
review: https://review.kiji.org/r/1002
EXP-189. Add a cleanup method to the score producer.

There are tables and resources that are opened during the setup of the producer
but not closed hence throwing exceptions in the finalizer if the producer is in
a long running process. This adds a cleanup method to close and release
resources.

Reviewer: robert
EXP-130. Implement an API for running valid subsets of model lifecycle phases.

review: https://review.kiji.org/r/1022
issue: https://jira.kiji.org/EXP-130
Contrived iterative prepare job.

Reviewed by: robert
EXP-173. Users need to be able to page through columns with many versions.
Users of express may now request that column paging be enabled. If paging
is enabled, a PagedKijiSlice is returned in the associated tuple field. A
PagedKijiSlice allows users to iterate over all cells in a column, while
limiting the number of cells in memory.

Reviewed By: Robert Chu
EXP-192. Ensure that phase classes can be properly loaded.

This will ensure that phase classes can be loaded from the right classloaders
instead of just restricting to the class loader of the code executing the
Class.forName method call.

Reviewer: robertchu
EXP-178. Get rid of all Avro unions in ModelDef and ModelEnv

issue: https://jira.kiji.org/browse/EXP-178
review: https://review.kiji.org/r/1021
Fixes regression test hanging

by increasing permgen space for the scalatest jvm

reviewed by: robertchu
EXP-132. Extend model definitions and environments to allow users to specify PMML to use for model.

issue: https://jira.kiji.org/browse/EXP-132
review: https://review.kiji.org/r/1058
EXP-194. Allow multiple inputs/outputs to a single phase of the model lifecycle

issue: https://jira.kiji.org/browse/EXP-194
review: https://review.kiji.org/r/1054
EXP-195. Add support for Text Input/Output sources in the Modeling Lifecycle.

issue: https://jira.kiji.org/browse/EXP-195
review: https://review.kiji.org/r/1063/
POM-22. Release root pom version 1.1.3

issue: https://jira.kiji.org/browse/POM-22
review: https://review.kiji.org/r/1084
EXP-201. AvroValue should include an Avro SpecificRecord implementation

issue: https://jira.kiji.org/browse/EXP-201
review: https://review.kiji.org/r/1076
EXP-145. Allow EntityIdFactoryCache to accept a Configuration

issue: https://jira.kiji.org/browse/EXP-145
review: https://review.kiji.org/r/1075
EXP-202. Express script should pass hadoop flags to Hadoop's GenericOptionsParser.

issue: https://jira.kiji.org/browse/EXP-202
review: https://review.kiji.org/r/1100
EXP-136. Implement a trainer for linear regression models.

issue: https://jira.kiji.org/browse/EXP-136
review: https://review.kiji.org/r/1125