Change semantics of CircularBuffer

Now it is more like a queue with a fixed capacity.
Add identifiers for slots in txbuf
Change how transmitter sends packets

* It adds many packets to the buffer at once.
* The time is changed to just before it processes the buffer.
Remove frame.error if Math.random() < this.p
Change default parameters
Display windows
Replace d3.timer with chained setTimeout

Timing is inaccurate with d3.timer and cannot be fixed.
Fix resize
Remove unused condition
Change default parameters
Merge branch 'd3-transition'

Major changes include displaying windows and applying transitions.
Fix svg width bug for Firefox
Check for uninitialized values when resizing
Fix svg overflowing in IE
Fix variable name collision in IE
Fix margin
Merge branch 'browser-compatibility'
Fix legend being too wide