This is a prototype 'card reader' program intended for use in an access system for
opening doors with NFC. 


Requirements:
- a NFC reader that works with libnfc
- a MiFare Classic 1K card. 
- libnfc and libfreefare
- libcurl 
- the accompanying 'backend/server' program
- SSL certificate authentication configured on the server, and corresponding
  copies of the CA and client certificates

See http://www.hackmelbourne.org/wiki/index.php/Project/Access_System/Installation_Instructions 
for more detailed installation instructions

There are hooks in action.c for actions that take place when a valid or
invalid card is presented. For now, this just involves sending either 
'v' (valid) or 'i' (invalid) over the serial port, i.e to an Arduino
that blinks a LED. 
The intention is to have a modular interface so different ways of 
triggering a door-latch mechanism can be used.