Here are some useful links.

Git

• https://guides.github.com/activities/hello-world/
• https://www.atlassian.com/git/tutorials/

JavaScript

Tutorials

• http://www.codecademy.com/en/tracks/javascript
• https://developer.mozilla.org/en-US/docs/Web/JavaScript

Static Analysis

• http://jshint.com/

Game Engine

• http://cutjs.org/

Cross-platform porting tools

• http://docs.phonegap.com/en/edge/guide_platforms_index.md.html
• https://cordova.apache.org/

Multiplayer

• https://developer.mozilla.org/en-US/docs/WebSockets
• http://peerjs.com/

Jekyll

• http://jekyllrb.com/