TO START:
- Compile all .erl files with erlc
- Open two command prompts, A and B

LINK DEMO:
- In prompt A, run link_remote.pl
- In prompt B, run link_local.pl
- Kill link_rempote.pl, see tick process restart on B
- Kill link_local.pl on A, restart linK_remote.pl on B
- Run   link_local.pl 2   on B, see normal termination
- Run   link_local.pl 3   on B, see exception termination

UPDATE DEMO:
- In prompt A, run update_start.pl, watch it tick
- In prompt B, run   update.pl 2   and see code switch to module 2
- In prompt B, run   update.pl 1   and see code switch to module 1

