add delete_rosters to delete big roster
add delete_rosters to delete big roster

zhangchaoeasemob/erl_tool,zhangchaoeasemob/erl_tool,zhuxiangkui/erl_tool,zhangchaoeasemob/erl_tool,zhuxiangkui/erl_tool,zhuxiangkui/erl_tool,wcy123/erl_tool,zhuxiangkui/erl_tool,wcy123/erl_tool,wcy123/erl_tool,zhangchaoeasemob/erl_tool,zhuxiangkui/erl_tool,wcy123/erl_tool,wcy123/erl_tool,zhangchaoeasemob/erl_tool