SCHEMA-238. Adds a deprecation warning for new tables created with RowKe...

...yFormat.

Testing done: mvn clean verify. Building a bento box with this and testing:

```
$ bin/kiji create-table --table=kiji://.env/default/foods --layout=/home/milo/kiji/kiji-schema/kiji-schema/src/test/resources/org/kiji/schema/layout/foods.json

Parsing table layout: /home/milo/kiji/kiji-schema/kiji-schema/src/test/resources/org/kiji/schema/layout/foods.json
Creating Kiji table kiji://localhost:2183/default/foods/
13/03/12 15:57:07 WARN org.kiji.schema.impl.HBaseKiji: Usage of 'RowKeyFormat' is deprecated. New tables should use 'RowKeyFormat2'.
```

Note that this change is a partial patch for SCHEMA-238 and the the pull request should be added to the comments, but the issue should not be marked as resolved until we resolve the other subtasks.