Repo refactoring

Hi,

This is a proposal for refactoring the repo structure.

The idea is to have subprojects such as:

 - openbus-broker: all things related with kafka and AVRO
 - openbus-batch: all things related with Hadoop, Camus, Hive, Pig, Mapreduce...
 - openbus-realtime: all things related with Storm

Please @juliansimon  and @ficastinger review if this structure is ok for you because it could impact future merges of ongoing branches.

It's just renaming and organizing but we should agree with this change.

any suggestions or feedback welcome!