added release script

release.sh

@@ -0,0 +1,27 @@
+#!/usr/bin/env bash
+
+set -e
+
+if [[ $# -eq 0 ]] ; then
+    echo 'version not provided: "./release.sh <VERSION>"'
+    exit 1
+fi
+
+NEW_VERSION=$1
+BRANCH_NAME=prepare-version-${NEW_VERSION}
+
+# prepare master branch
+git fetch
+git checkout master
+if [ ! -z "$(git status --untracked-files=no --porcelain)" ]; then 
+  echo "there are uncommitted changes in tracked files"
+  exit 1
+fi
+
+# update version 
+npm version --no-git-tag-version ${NEW_VERSION}
+git commit package.json package-lock.json -m "updated version to ${NEW_VERSION}"
+git push origin master
+
+# create release
+hub release create ${NEW_VERSION} -m "${NEW_VERSION}"