README: tell people where to find people in slack
README: tell people where to find people in slack

jhjeong-kr/cadvisor,erSitzt/cadvisor,erSitzt/cadvisor,erSitzt/cadvisor,ncdc/cadvisor,derekwaynecarr/cadvisor,f0/cadvisor,f0/cadvisor,BrickXu/cadvisor,jhjeong-kr/cadvisor,jhjeong-kr/cadvisor,BrickXu/cadvisor,ncdc/cadvisor,f0/cadvisor,derekwaynecarr/cadvisor,dchen1107/cadvisor,derekwaynecarr/cadvisor,f0/cadvisor,linux-on-ibm-z/cadvisor,BrickXu/cadvisor,jhjeong-kr/cadvisor,ncdc/cadvisor,erSitzt/cadvisor,ncdc/cadvisor,jhjeong-kr/cadvisor,derekwaynecarr/cadvisor,dchen1107/cadvisor,ncdc/cadvisor,dchen1107/cadvisor,linux-on-ibm-z/cadvisor,dchen1107/cadvisor,BrickXu/cadvisor,derekwaynecarr/cadvisor,BrickXu/cadvisor,erSitzt/cadvisor,dchen1107/cadvisor,f0/cadvisor,linux-on-ibm-z/cadvisor