Fix System.out.print(String)

Hello Phil,

please merge this System.out.print(String) fix.

You deleted the ```int curr_offset;``` in GarbageCollector.c [1]

```
generated.cu(252): error: identifier "curr_offset" is undefined
```

Thanks!

Martin

[1] https://github.com/pcpratts/rootbeer1/blob/master/src/org/trifort/rootbeer/generate/opencl/GarbageCollector.c#L587