fix bug: starting project failed if no tasks
fix bug: starting project failed if no tasks

snakeliwei/pyspider,binux/pyspider,VDuda/pyspider,luotao19861229/pyspider,nicozhang/pyspider,snakeliwei/pyspider,luotao19861229/pyspider,lashwang/pyspider,e-dorigatti/pyspider,wangjun/pyspider,qiulimao/weblocust,eromoe/pyspider,luoq/pyspider,snakeliwei/pyspider,wonderay/pyspider,qiulimao/weblocust,e-dorigatti/pyspider,VDuda/pyspider,nicozhang/pyspider,e-dorigatti/pyspider,wangjun/pyspider,luotao19861229/pyspider,wonderay/pyspider,luoq/pyspider,binux/pyspider,eromoe/pyspider,binux/pyspider,VDuda/pyspider,lashwang/pyspider,nicozhang/pyspider,luoq/pyspider,qiulimao/weblocust,wangjun/pyspider,lashwang/pyspider,eromoe/pyspider,wonderay/pyspider