Always call prepare corpus so that we can concat multiple --corpora even with --no-prepare
Always call prepare corpus so that we can concat multiple --corpora even with --no-prepare

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