Refactored dockerfile

Signed-off-by: Andrew DeMaria <lostonamountain@gmail.com>

install/docker/Dockerfile

@@ -3,25 +3,27 @@ FROM alpine:3.6
 LABEL description="Airsonic is a free, web-based media streamer, providing ubiquitious access to your music." \
       url="https://github.com/airsonic/airsonic"
 
-ENV UID=1001 GID=1001 AIRSONIC_PORT=4040 AIRSONIC_DIR=/airsonic
+ENV AIRSONIC_PORT=4040 AIRSONIC_DIR=/airsonic
 
 WORKDIR $AIRSONIC_DIR
 
-COPY dockerfiles/run.sh /usr/local/bin/run.sh
-COPY target/dependency/airsonic-main-6.3-SNAPSHOT.war airsonic.war
-
 RUN apk --no-cache add \
     ffmpeg \
     lame \
-    su-exec \
+    bash \
     libressl \
     ca-certificates \
     tini \
-    openjdk8-jre \
-    && chmod +x /usr/local/bin/run.sh
+    openjdk8-jre
+
+COPY run.sh /usr/local/bin/run.sh
+
+RUN chmod +x /usr/local/bin/run.sh
+
+COPY target/dependency/airsonic-main-6.3-SNAPSHOT.war airsonic.war
 
 EXPOSE $AIRSONIC_PORT
 
 VOLUME $AIRSONIC_DIR/data $AIRSONIC_DIR/music $AIRSONIC_DIR/playlists $AIRSONIC_DIR/podcasts
 
-ENTRYPOINT ["run.sh"]
+ENTRYPOINT ["tini", "--", "run.sh"]