[CDF-213]: Turned robochef into a proper ivy dependency

@lcheng-pentaho @lgrill-pentaho @smaring @jgrajewski
Dependency changes for your review

The robochef dependency jar was checked-in. It was removed and added to the ivy.xml as a proper dependency.

Had to setup a ci job for building the robochef project and publish it to the Pentaho repository (http://ci.pentaho.com/job/kettle-robochef). Robochef is a small utility that will not change over time, so I think it does not need nightly or release builds.