Keep Snap fullnode/drone logs out of syslog, we're too spammy

ci/docker-snapcraft/Dockerfile

@@ -2,6 +2,6 @@ FROM snapcraft/xenial-amd64
 
 # Update snapcraft to latest version
 RUN apt-get update -qq \
- && apt-get install -y snapcraft \
+ && apt-get install -y snapcraft daemontools \
  && rm -rf /var/lib/apt/lists/* \
  && snapcraft --version

ci/snap.sh

@@ -37,6 +37,12 @@ fi
 
 set -x
 
+echo --- checking for multilog
+if [[ ! -x /usr/bin/multilog ]]; then
+  echo "multilog not found, install with: sudo apt-get install -y daemontools"
+  exit 1
+fi
+
 echo --- build
 snapcraft