SCHEMA-328. Fix CellSpec javadoc.

issue: https://jira.kiji.org/browse/SCHEMA-328
review: https://review.kiji.org/r/294
Updates release notes for 1.0.2.
[maven-release-plugin] prepare release kiji-schema-root-1.0.2
[maven-release-plugin] prepare for next development iteration
SCHEMA-324. Load Hadoop distro-specific jars in bin/kiji

Using 'hadoop version', it selects the appropriate jar dir under
$KIJI_HOME/lib/distribution/ to put on the classpath.
SCHEMA-187. CellSpec must handle generic records (eg. when generated Avro classes are not available)

This change fixes the reader side of SCHEMA-187 only.
The writer side will be fixed in another issue/change.

- CellSpec now has a "no reader schema" mode (ie. use writer schema).
- Cell decoders use the writer schema/generic records when specific classes are not available.
- No unit-test added yet (we cannot write generic records yet).
I tested this change manually using the KijiMusic end-to-end test, running kiji scan on the
songs table without the SongMetadata specific record on the classpath.

issue: https://jira.kiji.org/browse/SCHEMA-187
review: https://review.kiji.org/r/290
SCHEMA-329. Remove HBaseKijiRowData.merge().

issue: https://jira.kiji.org/browse/SCHEMA-329
review: https://review.kiji.org/r/297
SCHEMA-330. Adds default values to Node/Edge test records.

- Allows using builders without hassle in unit-tests.

issue: https://jira.kiji.org/browse/SCHEMA-330
review: https://review.kiji.org/r/298