Recursion Bug with GC

The GC is not working properly when there is recursion. [See the Code](https://github.com/CondorLang/Condor/blob/master/src/condor/execute/execute.cc)
## Example Code:

``` go
import "println" from "console"
func fib(int n){
    println("-> " + n);
    if (n == 0) return 0;
    else if (n == 1) return 1;
    else return fib(n - 1) + fib(n - 2);
}

int val = fib(2);
println(val);
```
