added publish script (to upload images to dockerhub)

publish.sh

@@ -0,0 +1,31 @@
+#!/bin/bash
+
+while getopts v: option
+do
+case "${option}"
+in
+v) VERSION=${OPTARG};;
+esac
+done
+
+if [ -z "$VERSION" ]
+then
+	echo "Please provide a valid version with the -v flag. e.g: -v 1.0"
+	exit 1
+fi
+
+echo "This will upload a new signal-cli-rest-api to dockerhub"
+echo "Version: $VERSION"
+echo ""
+
+read -r -p "Are you sure? [y/N] " response
+case "$response" in
+    [yY][eE][sS]|[yY])
+        docker buildx build --platform linux/amd64,linux/arm64 -t bbernhard/signal-cli-rest-api:$VERSION .
+		docker buildx build --platform linux/amd64,linux/arm64 -t bbernhard/signal-cli-rest-api:latest .
+        ;;
+    *)
+        echo "Aborting"
+		exit 1
+        ;;
+esac