minor changes for balance board setup
handle upper-case hex macs
add new bboard mac, implement radial gradient display

Uses CSS radial gradients on the background div to display orientation
on the balance board.
remove dead code
center the gradient on lack of input

When the database has no data, the webserver will send a zeroed
structure. Before this change, the gradient would rest at 355,355
(hardcoded for now). Now when direction === "", the percentage
values are forced to 25% which causes the gradient to be centered.

Also added a newline to the style line.
add colors to match tile values with alpha
rename upper right corner cell, remove AI stats
add css for rendering svg graph with d3
add pressure graph, rearrange grids, fix a few bugs

Most of the code is implementing the upper right hand corner
graph with straight D3 since Dimple.js was getting in the way.

It looks cool, but it's not quite right. Something to look into later.

Swapped the AI board with player2 so human players are on the
left & right.

Removed some dead code.

Moved the centering code into the websocket handler so it can also
cover the upper right hand corner graph.

Changed the colors a little for the background gradient.
update colors
make the game grids bigger
add sbt assembly plugin & configure it