Dependency Updates

This release just bumps dependencies to enable and test support for Numba 0.56; also bumps up the minimum SciPy version to make the tests pass reliably (the minimum version is still several years old).

What's Changed

• Use external build tools for 0.14 fix releases by @mdekstrand in #321
• Support Numba 0.56 in 0.14 series by @mdekstrand in #322

Full Changelog: 0.14.1...0.14.2