Docker fixes as per review.

docker-library/official-images#4987 (comment)

Revert to stderr logging.
Use wget instead of curl.
Don't redownload libuuid or libwebsockets.

docker/1.5/Dockerfile

@@ -10,14 +10,13 @@ ENV VERSION=1.5.3 \
 RUN set -x && \
  apk --no-cache add --virtual build-deps \
  build-base \
- curl \
  gnupg \
  libressl-dev \
  libwebsockets-dev \
  util-linux-dev && \
- curl -fSL https://mosquitto.org/files/source/mosquitto-${VERSION}.tar.gz -o /tmp/mosq.tar.gz && \
+ wget https://mosquitto.org/files/source/mosquitto-${VERSION}.tar.gz -O /tmp/mosq.tar.gz && \
  echo "$DOWNLOAD_SHA256 /tmp/mosq.tar.gz" | sha256sum -c - && \
- curl -fSL https://mosquitto.org/files/source/mosquitto-${VERSION}.tar.gz.asc -o /tmp/mosq.tar.gz.asc && \
+ wget https://mosquitto.org/files/source/mosquitto-${VERSION}.tar.gz.asc -O /tmp/mosq.tar.gz.asc && \
  export GNUPGHOME="$(mktemp -d)" && \
  found=''; \
  for server in \
@@ -53,12 +52,11 @@ RUN set -x && \
  install -d /usr/sbin/ && \
  install -s -m755 /build/src/mosquitto /usr/sbin/mosquitto && \
  install -m644 /build/mosquitto.conf /mosquitto/config/mosquitto.conf && \
- sed -i -e 's/#log_dest stderr/log_dest syslog/' /mosquitto/config/mosquitto.conf && \
  chown -R mosquitto:mosquitto /mosquitto && \
- apk del build-deps && \
  apk --no-cache add \
  libuuid \
  libwebsockets && \
+ apk del build-deps && \
  rm -rf /build /etc/apk /lib/apk
 
 VOLUME ["/mosquitto/data", "/mosquitto/log"]