[TODO] UI Enhancement

[wenjie1991]

• [x] CSS for index.html.
• [x] Data loading gif waiting for animation for plot.html.
• [x] plot.html is dull ~ try to make it colorful. So CSS.
• [x] Suggestion(apologies) for IE user.
• [x] Adjust picture size.

[palmerye]

in feature branch.

• [x] add new index.html instead of.