Add first release

What's Changed

• Add a Gitter chat badge to README.md by @gitter-badger in #2
• Add more help and add sticker msg event by @kkdai in #19

New Contributors

• @gitter-badger made their first contribution in #2
• @kkdai made their first contribution in #19

Full Changelog: https://github.com/kkdai/LineBotTemplate/commits/v.0.1.0