update description about report api.
update description about report api.

war22moon/jpush-docs,xiongtiancheng/jpush-docs,war22moon/jpush-docs,jpush/jpush-docs,Aoyunyun/jpush-docs,xiongtiancheng/jpush-docs,xiongtiancheng/jpush-docs,raoxudong/jpush-docs,raoxudong/jpush-docs,jpush/jpush-docs,Aoyunyun/jpush-docs,jpush/jpush-docs,raoxudong/jpush-docs,raoxudong/jpush-docs,xiongtiancheng/jpush-docs,Aoyunyun/jpush-docs,Aoyunyun/jpush-docs,jpush/jpush-docs,war22moon/jpush-docs,war22moon/jpush-docs