FLUID-5516: Updated build site to match new design.

@jobara @acheetham - I've updated the build site to match the new designs. Can you check to make sure I got all the right demos and that the links all go to the right places?
I think adding a link to the How to Create and Use Icon Fonts tutorial would address this.
https://github.com/fluid-project/infusion-docs/blob/master/src/documents/tutorial-creatingANewAdjusterUI/HowToCreateAndUseFontIcons.md

Thoughts?