add packages

Dockerfile

@@ -5,6 +5,7 @@ MAINTAINER PlusMinus <piddlpiddl@gmail.com>
 
 # Create directory, and start JD2 for the initial update and creation of config files.
 RUN \
+    apk add --no-cache --quiet tini su-exec bash && \
 	mkdir -p /opt/JDownloader/ && \
 	wget -O /opt/JDownloader/JDownloader.jar --user-agent="https://hub.docker.com/r/plusminus/jdownloader2-headless/" --progress=bar:force http://installer.jdownloader.org/JDownloader.jar && \
 	java -Djava.awt.headless=true -jar /opt/JDownloader/JDownloader.jar