Color and multi-class support

This minor release adds pretrained color models (i.e. with 3 channels) and also adds support for multi-class finetuning.

What's Changed

• sync by @mwalmsley in #92
• 1.0.3 version bump by @mwalmsley in #99
• Rebuild docs by @mwalmsley in #103
• Add color weights, trivial QoL changes by @mwalmsley in #104
• Add multiclass example by @mwalmsley in #105
• Add multiclass support by @mwalmsley in #106

Full Changelog: v1.0.3...v1.0.4