added docker xfce4

.docker/files/xfce4/Dockerfile

@@ -0,0 +1,11 @@
+FROM nurdism/neko:base
+
+#
+# install xfce4
+RUN set -eux; apt-get update; \
+    apt-get install -y --no-install-recommends xfce4;
+
+#
+# copy xfce4 conf and supervisord conf
+COPY .docker/files/xfce4/supervisord.conf /etc/neko/openbox.xml
+# COPY .docker/files/xfce4/xfconf /etc/neko/xfconf

.docker/files/xfce4/supervisord.conf

@@ -0,0 +1,10 @@
+[program:xfce4]
+environment=HOME="/home/%(ENV_USER)s",USER="%(ENV_USER)s",DISPLAY="%(ENV_DISPLAY)s"
+command=/usr/bin/xfce4-session
+autorestart=true
+priority=300
+user=%(ENV_USER)s
+stdout_logfile=/var/log/neko/xfce4.log
+stdout_logfile_maxbytes=100MB
+stdout_logfile_backups=10
+redirect_stderr=true