Add `make server` command to preview docs
Add Mac OS X instructions for doc tools
Make style consistent
Add more tags
Fix typo
Use em dash in title
Use title case for consistency
Name examples consistently
Use code blocks
Add Node.js web app example using CentOS
Add link at the beginning
Document installation of npm dependencies /ht @grigio
Merge pull request #787 from gasi/nodejs-centos-docs

* Documentation: Deploying a Node.js Web App on CentOS
* Documentation: small formatting improvements