v0.4.0

This feature release provides a simple ColorPair type that can to extended in the future (for low contrast detection, for instance).

We also made all color types hashable, breaking change, since they must be immutable.

Update the library using pip:

$ pip install -U ochre

What's Changed

• Increased the robustness of color comparisons (fec9475, 5d52977, 4d001d3)
• Added the ColorPair type (a3408b0)
• Made all concrete types immutable and hashable (8e666f1, 588b033)
• Bump pytest to 6.2.5 by @dependabot in #19
• Bump hypothesis to 6.31.6 by @dependabot in #25
• Bump mypy to 0.920 by @dependabot in #26