Now we detect whether the user can play or not.
And we raise the proper messages for each case
Added a message to show the player a lack of credits.
Win credits are calculated and added.
getWin has been renamed to getPrize
Traces have been improved, but credits are not working fine.
Traces have been improved, but credits are not working fine.
The Slot Machine is fully operational.

I've implemented all the logic from the original slot machine (by the
way I've added the original version here as well).

I've found a problem which (I believe) is related to simultaneous
events. The thing is that when you play a game and you win, you spend
one credit and you receive several of them. It seems that the later
part was being ignored, unless the first part was commented (in the
event `union` combination). In that case, the prize is added
smoothly. So, this is something to take into account in order to
determine how easy is to develop an application.
Merge pull request #71 from jeslg/slot-banana

Slot banana