Colored protein diagrams

[eweitz]

Gene leads ideogram now has colored protein domains. It lets you easily assess how a gene’s functional units are organized.

In the LDLR gene, for example, you can quickly discern how the protein consists largely of class A repeats – in orange – and class B repeats – in beige. This enhances #334.

Here's a narrated demo explaining how it works -- unmute audio at lower right to hear:

https://user-images.githubusercontent.com/1334561/210685363-0ece7ad3-6bd5-4c3c-9b87-e74967b3d517.mp4

[coveralls]

Coverage: 86.549% (-0.1%) from 86.68% when pulling 21f127603715dd3c58f8b2fd3beebc154fbde363 on protein-colors into f8ece53241592421326e4a376dca724ddb46209d on master.