KIJIMR-174. kiji-avro dependency moved to lib/distribution/hadoop*/.

* Incorporates KIJIMR-177. Enable hadoop1.x compilation module.
* All tests now pass in the mr-hadoop1x module: This should support Hadoop 1.0.x.
* Sets minimum HBase version requirement in Hadoop 1.x to HBase 0.94.7.
* Adds SequenceFile reader shim required by tests.
* Moves kiji-avro jar dependency into distribution-specific packaging;
  hadoop1 and hadoop2-based KijiMR builds depend on different versions of kiji-avro.