Zigduino delay

[Pierce Nichols]

Our source of Atmega128RFA1s seems to have dried up, which means that
the Zigduino will be delayed. Digikey claims that they will ship the
parts on Apr 2; if they meet this deadline, we will be able to start
shipping Zigduinos by the end of April. It's terribly frustrating for
me, because I have everything else lined up and ready to go.

Since I now have a month to twiddle my thumbs while I wait for parts,
I'm filling it up by updating documentation, software, and my testing
procedure. I've posted an updated schematic and an overview of the
board layout, and I'm also fleshing out the Zigduino product page on
the pattern of the Arduino Uno hardware page.

I'm also considering some changes to reduce the power consumption. The
easiest one has been swapping in a 3.3V regulator with a lower
quiescent current. I'm planning on powering the FTDI chip (which is
kind of a pig -- it's half of the power consumption) off the USB bus,
since it doesn't need power unless it's hooked to USB. I'm also
considering fiddling with some other things to reduce the current
consumption. Does anyone require particularly low power consumption?