Consider ANSI escape codes when calculating content width

[lread]

Problem

I'd love to sometimes add some color to my tables.
But when I do Doric doesn't render my table properly.

Cause

Doric does not consider ANSI escape codes when calculating the content length.
These codes take up no space, but Doric thinks they do.

Next Steps

Like the idea? After we flesh out any details, I'd be happy to create a PR.