Start off with an account module
Add the ability to deposit money
Add withdrawal, make balance checking smarter
Add beginnings of Atm module
Add support for fetching balance, etc
Fix some of the public api

realllly unhappy with some of this, but it's a learning exercise amirite
Looks like step 1's implented, though I'm not a fan

Way too much awkwardness in the Atm module, need to figure out how to
write this stuff more appropriately before I'll be happy with it.
Playing with global gproc, failing
Revert "Playing with global gproc, failing"

Cannot get global gproc working in elixir, unsure how to pass the flag
to it :(

This reverts commit 34368735e165bc716990da50e2d21fc8e13fbe99.
Merge pull request #4 from knewter/master

Include josh adams' ATM step1