Small modifications in orka/README.md
Small modifications in orka/README.md

ibyron/e-science,KPetsas/e-science,ibyron/e-science,ioannisstenos/e-science,grnet/e-science,ioannisstenos/e-science,ibyron/e-science,ibyron/e-science,grnet/e-science,grnet/e-science,ioannisstenos/e-science,ioannisstenos/e-science,KPetsas/e-science,ioannisstenos/e-science,KPetsas/e-science,KPetsas/e-science,ibyron/e-science,grnet/e-science,grnet/e-science,KPetsas/e-science