add Dockerfile

Author: zhangchunsheng

bin/entrypoint.sh

@@ -174,7 +174,7 @@ HELP
 
 function main() {
   # issue #84
-  echo -e 'nameserver 114.114.114.114\nnameserver 1.1.1.1\nnameserver 8.8.8.8' | sudo tee -a /etc/resolv.conf > /dev/null
+  echo -e 'nameserver 114.114.114.114\nnameserver 1.1.1.1\nnameserver 8.8.8.8' >> /etc/resolv.conf > /dev/null
 
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