Major code reorganization to the new knobs and on-off switches.
Add a play/pause button image that toggles when clicked.

Signed-off-by: Matthew Price <hello@mattprice.me>
Change the footer font color to white.
Hide the download button until it gets implemented.
Wrap the track controls so that they vertically center correctly.

Centering the controls previously required some nasty hard-coded CSS
hacks to the element's height and padding. Not anymore!
Shrink the height of each track; fix alignment issues in Firefox, IE.
Add some padding to the footer.
Chrome: Don't outline the play button when clicked.
Firefox: Set the font color of the presets select list to black.

Apparently Firefox let's you modify the font color of a select list
even though that makes it completely unreadable. Since the main font
color of the footer was white, that made the select list have white
font too.
Add example track names.
Fix a bug that caused RAMP to always load the remote tracks file.
Add a fallback for scrolling the controls in IE. Fixes #1.