Fixed 'exports' to 'export'
New vm_stock

Not sure if thats what you expected, please review it:)
Functionality of VM_STOCK on List
vm_stock, vm_case, vm_coincase ready as gen_servers
vm_coin almost working, todo calculating change
Fixed server stop
vm_coin with working change algorithm

to removing the returned coins from coin stock
working vm_coin
Merge branch 'magda'
Merge branch 'pawel' of https://github.com/haljin/robust into pawel
Added records
State machine'd