added running dog image for documentation.
added running dog image for documentation.

tingletech/rexster-tomcat,alszeb/rexster,alszeb/rexster,tingletech/rexster-tomcat,alszeb/rexster,tomgullo/rexster,tomgullo/rexster,alszeb/rexster,tomgullo/rexster,tomgullo/rexster,tingletech/rexster-tomcat