Integer division / std.trunc ?

It's easy to get the remainder when dividing two integers:

```
$ jsonnet -e -- '105 % 100'
5
$ jsonnet -e -- '-105 % 100'
-5
```

But I found it unexpectedly awkward to do the actual division:

```
$ jsonnet -e -- 'std.floor(105 / 100)'
1
$ jsonnet -e -- 'std.floor(-105 / 100)'
-2
```

In javascript there would be `Math.trunc` for this. Of course, you can write it yourself if you need it.

I wonder if `std.trunc` would be a useful addition? Or `std.div` for integer division?