add travis icon to readme
add travis icon to readme

hughperkins/DeepCL,MiniLight/DeepCL,MiniLight/DeepCL,hughperkins/DeepCL,hughperkins/DeepCL,MiniLight/DeepCL,MiniLight/DeepCL,MiniLight/DeepCL,hughperkins/DeepCL,hughperkins/DeepCL