Add guetzli (#248)

guetzli/Dockerfile

@@ -0,0 +1,37 @@
+# guetzli
+#
+# docker run \
+#			--rm \
+#			-i \
+#			-t \
+#			-v ${PWD}:/tmp \
+#			guetzli:latest \
+#			--verbose /tmp/example.jpg /tmp/example.compressed.jpg
+
+FROM alpine:latest
+LABEL maintainer "Christian Koep <christian.koep@fom-net.de>"
+
+ENV GUETZLI_VERSION v1.0.1
+ENV APPDIR /usr/src/guetzli
+
+RUN buildDeps=' \
+                g++ \
+                git \
+                libpng-dev \
+                make \
+	' \
+	set -x \
+	&& apk --no-cache add $buildDeps \
+	&& git clone --depth 1 --branch ${GUETZLI_VERSION} https://github.com/google/guetzli.git ${APPDIR} \
+	&& cd ${APPDIR} \
+	&& make \
+	&& apk del $buildDeps \
+	&& mv ${APPDIR}/bin/Release/guetzli /usr/local/bin/guetzli && rm -rf ${APPDIR} \
+	&& echo "Build complete."
+
+RUN apk --no-cache add \
+		libpng \
+		libstdc++ \
+		libgcc
+
+ENTRYPOINT [ "/usr/local/bin/guetzli" ]