reading working for primitive types
remove AvroValues types
Merge pull request #1 from robotoer/exp-222-take3

Added Kryo serializers for avro.
Merge branch 'exp-222-take3' of github.com:danburkert/kiji-express into exp-222-take3

Conflicts:
	src/test/scala/org/kiji/express/util/ReturnTypeCheckerSuite.scala
add SchemaSpec trait to specify how to read or write data
small fix for test error.