updated readme. Add cell subclassing section
updated readme. Add cell subclassing section

xmartlabs/Eureka,thierrybucco/Eureka,jpvasquez/Eureka,HassanEskandari/Eureka,xmartlabs/Eureka,jpvasquez/Eureka,JackEsad/Eureka,thierrybucco/Eureka,btanner/Eureka,JackEsad/Eureka,btanner/Eureka,HassanEskandari/Eureka