use none-root user for docker

specified sshhost can not login as root

Dockerfile

@@ -8,6 +8,8 @@ RUN apt-get update
 RUN apt-get install -y vim
 RUN useradd -d /home/term -m -s /bin/bash term
 RUN echo 'term:term' | chpasswd
+RUN chown -R term:term /app
+USER term
 
 EXPOSE 3000