Deploy hexo to Elastic BeanStalk

Extremely difficult process.

The old hexo-deployer-git requires hexo-util@0.5.3 triggers permission errors all the time. Updating hexo-deployer-git can solve the problem.

After npm install hexo -g, the ec2 instance still post error hexo: command not found. Adding a Procfile with web: /opt/elasticbeanstalk/node-install/node-v12.16.3-linux-x64/lib/node_modules/hexo/bin/hexo server -p 8080 solves the issue.