Import/Export CSV

Might need to add the ability to import CSV files, depending on whether they've already used Excel to make their inventory.
Good advice, thanks man. I actually am familiar with the bang operator and in the original code I had saved the raw input into the variable then used the strip! method to change it in place. At some point I just did it simultaneously and forgot to take the bang operator out. Not sure if you know this, but strip! will actually return nil if there is nothing to strip.

```ruby
s = "hello".strip!
```
s would be nil.

We should start the old blog back and you should post things like this...this is actually really helpful.