Upgrade etherpad

pica-eterpad/Dockerfile

 FROM registry.picasoft.net:5000/pica-debian:latest
 MAINTAINER antoine@barbare.me
 
-ENV ETHERPAD_VERSION 1.6.0
+ENV ETHERPAD_VERSION 1.6.1
+
+#Installation de NodeJS + NPM
+RUN curl -sL https://deb.nodesource.com/setup_8.x | bash - && \
+    apt-get install -y nodejs
 
 RUN apt-get update && \
-    apt-get install -y unzip nodejs-legacy npm mysql-client supervisor && \
+    apt-get install -y unzip mysql-client supervisor && \
     rm -r /var/lib/apt/lists/*
 
 WORKDIR /opt/