Update README to include instruction to run ant devel first.
Update README to include instruction to run ant devel first.

fhieber/incubator-joshua,lukeorland/joshua,lukeorland/joshua,thammegowda/incubator-joshua,thammegowda/incubator-joshua,thammegowda/incubator-joshua,lukeorland/joshua,lukeorland/joshua,fhieber/incubator-joshua,thammegowda/incubator-joshua,thammegowda/incubator-joshua,lukeorland/joshua,fhieber/incubator-joshua,thammegowda/incubator-joshua,lukeorland/joshua,fhieber/incubator-joshua,lukeorland/joshua,fhieber/incubator-joshua,fhieber/incubator-joshua,thammegowda/incubator-joshua,fhieber/incubator-joshua,thammegowda/incubator-joshua,thammegowda/incubator-joshua,lukeorland/joshua,fhieber/incubator-joshua,thammegowda/incubator-joshua,lukeorland/joshua,fhieber/incubator-joshua