modify the usage of docker version

- 修改了uvloop下载源
- 修改Dockerfile中的入口
- 修改了README中docker版的使用说明

Dockerfile

@@ -4,13 +4,14 @@ MAINTAINER milktea@vmoe.info
 RUN sed -i 's/dl-cdn.alpinelinux.org/mirrors.aliyun.com/g' /etc/apk/repositories
 RUN apk update && apk --no-cache add git build-base libffi-dev libxml2-dev libxslt-dev libressl-dev
 ADD requirements.txt /requirements.txt
-RUN pip install uvloop
+RUN pip install uvloop -i https://mirrors.aliyun.com/pypi/simple/
 RUN pip install -r /requirements.txt -i https://mirrors.aliyun.com/pypi/simple/
 RUN git clone https://github.com/blechschmidt/massdns
 WORKDIR /massdns
 RUN make 
 ADD . /OneForAll/
 RUN mv /massdns/bin/massdns /OneForAll/thirdparty/massdns/massdns_linux_x86_64
+RUN mkdir /OneForAll/results
 WORKDIR /OneForAll/
 
-ENTRYPOINT ["/bin/ash"]
+ENTRYPOINT ["python", "oneforall.py"]