PsiPy 0.3.1

What's Changed

• Fix units in in-situ sampling example by @dstansby in #57
• Add docs on using PLUTO/MAS interchangably by @dstansby in #59
• Fix multiple timestep sample data by @dstansby in #60
• Add mypy to pre-commit by @dstansby in #63
• Fix radial units in PLUTO outputs by @dstansby in #62
• Support loading > 3 digit timestamps for MAS by @dstansby in #65
• Return NaN for out of bounds sample coordinates by @dstansby in #68
• Add codecov config by @dstansby in #69
• Add example for sampling across timesteps by @dstansby in #67

Full Changelog: 0.3.0...0.3.1