add README and build scripts

scripts/build-container.sh

@@ -0,0 +1,18 @@
+#!/usr/bin/env bash
+
+IMAGE=${IMAGE:-demo-server:$(date +%F)}
+
+SCRIPTDIR=$(dirname $0)
+BASEDIR=$(dirname $SCRIPTDIR)
+
+ARGS=()
+
+if [ ! -z "$APK_MIRROR" ]; then
+    ARGS+=(--build-args APK_MIRROR=${APK_MIRROR})
+fi
+
+if [ ! -z "$CRATES_MIRROR" ]; then
+    ARGS+=(--build-args CRATES_MIRROR=${CRATES_MIRROR})
+fi
+
+docker build -t $IMAGE -f ${BASEDIR}/build/Dockerfile "${ARGS[@]}" ${BASEDIR}