Power over ethernet nixie clock with NTP synchronization

(Initial release)

This is an ATMEGA328 based nixie clock. It supports power over ethernet (802.3af compliant), and sychronizes the time over NTP.

Features:
	ATMEGA328 8 bit MCU
	ENC28J60 based 10Mbit ethernet
	LM5070 isolated flyback supply (48V in, 5v & 200V output)
	HV5812 HV shift registers to drive the nixies
	IN-12 nixie tubes
	Piezo beeper for alarm
	RTC with backup battery in case internet goes down forever
	CP2102 USB to serial converter for debugging (or whatever...)
	SPDT relay, for driving a horn or bell

Preliminary code is complete and unit is functional. The code is a modification of the tuxgraphics NTP LCD clock.

Being fairly new to SMPS design, I'm afraid the tiny EP13 transformer core is getting too hot. I might try to retrofit a slightly larger core.

To do: code for alarm setting (both via http and buttons on the clock), general polishing.
Software will be posted once complete.