Update travis configuration

.travis.yml

@@ -1,26 +1,24 @@
 language: node_js
 
+cache: yarn
+
 node_js:
   - 'stable'
   - '8'
 
 sudo: false
 
 script:
-  - npm run build
-  - npm run validate
-
-after_script:
-  - node_modules/.bin/coveralls < coverage/lcov.info
+  - yarn test
 
 before_deploy:
-  - npm run build:dist && node ./script/package-dist.js
+  - npm yarn build
 
 deploy:
   - provider: npm
     email: '[email protected]'
     api_key:
-      secure: ''
+      secure: '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'
     on:
       tags: true
       node: '8'

README.md

@@ -167,7 +167,7 @@ Will output:
 
 ### Production
 
-This library uses joi to validate the input config structure, but it's quite large.
+This library uses [Joi](https://github.com/hapijs/joi) to validate the input config structure, but it's quite large.
 That's why they are added within `process.env.NODE_ENV !== 'production'` checks, which means
 that your build process can strip it out.