v1.2.0

DitherPunk v1.2.0

Diff since v1.1.0

Closed issues:

• Add references to docs (#19)
• Add per-channel dithering (#23)
• Add more error diffusion methods (#27)
• Documentation error (#30)

Merged pull requests:

• Add references to docstrings (#21) (@adrhill)
• Add more error diffusion methods (#29) (@adrhill)
• Fix #30 (#31) (@Tinkerer-Zlosk)
• Add separate-space dithering (#32) (@adrhill)