fixed the issue #78 - only write pubished_date when resource is indeed published
fixed the issue #78 - only write pubished_date when resource is indeed published

hydroshare/hydroshare,hydroshare/hydroshare,ResearchSoftwareInstitute/MyHPOM,hydroshare/hydroshare,RENCI/xDCIShare,RENCI/xDCIShare,FescueFungiShare/hydroshare,ResearchSoftwareInstitute/MyHPOM,hydroshare/hydroshare,FescueFungiShare/hydroshare,RENCI/xDCIShare,RENCI/xDCIShare,FescueFungiShare/hydroshare,ResearchSoftwareInstitute/MyHPOM,FescueFungiShare/hydroshare,ResearchSoftwareInstitute/MyHPOM,RENCI/xDCIShare,FescueFungiShare/hydroshare,ResearchSoftwareInstitute/MyHPOM,hydroshare/hydroshare