Optimized and improved logo SVGs and PNGs.

Optimized SVGs by hand, ~80% size reduction.
Optimized SVGs for browsers, can now be rendered properly by Gecko- and
Webkit-based browsers.
Resized SVG page, shadow is no longer cut off to the right.
Switched tray icons for ones without the cut-off shadow.
Optimized and switched icons for the new ones.