Wrong indices in arrays not starting with 0

```nim
let y: array[1..5, int] = [1,2,3,4,5]
echo y[3..5]
```
Expected output (and old output):
```
[3,4,5]
```
Actual output in devel branch:
```
Traceback (most recent call last)
min.nim(2)               min
system.nim(3496)         []
system.nim(2753)         sysFatal
Error: unhandled exception: index out of bounds [IndexError]
```