📦 Add semantic-release setup (#1)

Adds `semantic-release` and custom preset packages, and a config file
for Travis CI. Also replaces `yorkie` with `husky` for git hooks.

Author: stormwarning

.travis.yml

@@ -0,0 +1,14 @@
+language: node_js
+cache:
+    directories:
+        - ~/.npm
+notifications:
+    email: false
+node_js:
+    - '10'
+    - '8'
+after_success:
+    - npx travis-deploy-once "npx semantic-release"
+branches:
+    except:
+        - /^v\d+\.\d+\.\d+$/

CHANGELOG.md

@@ -1,7 +1,7 @@
 # Change Log
 
-[![Keep a Changelog][img-changelog]][url-changelog]
-[![Semantic Versioning][img-semver]][url-semver]
+[![Keep a Changelog](https://img.shields.io/badge/keep%20a-changelog-ef5e39.svg?style=flat-square)](https://keepachangelog.com)
+[![Semantic Versioning](https://img.shields.io/badge/semantic-versioning-333333.svg?style=flat-square)](https://semver.org)
 
 All notable changes to this project will be documented in this file.
 
@@ -15,11 +15,3 @@ All notable changes to this project will be documented in this file.
 ## 0.1.0 — 2018-10-16
 
 ### 🎉 Initial project release
-
-[img-changelog]: https://img.shields.io/badge/keep-a%20changelog-ef5e39.svg?style=flat-square
-
-[img-semver]: https://img.shields.io/badge/semantic-versioning-333333.svg?style=flat-square
-
-[url-changelog]: https://keepachangelog.com
-
-[url-semver]: https://semver.org