Speeds up comparison on `Version` by ~2.5x, e.g.
```python
In [1]: v = spack.version.Version('1.0.0'); w = spack.version.Version('1.0.2')
In [2]: %timeit v < w
1.47 µs ± 5.59 ns per loop (mean ± std. dev. of 7 runs, 1000000 loops each)
535 ns ± 1.75 ns per loop (mean ± std. dev. of 7 runs, 1000000 loops each)
```