This required a lot of restructuring, which is why I won't
put this on another branch.
A part of the library which is updated in github but not yet at hackage,
is needed to continue. Specifically, the `Monoid` instance in
`Text.Layout.Table.Cell.Formatted` is needed to put together multiple
colored text in a table.
Among other things introduced, there is now our own `Formatted` type
which is used to await formatting until things like tables come up.
Compared to the earlier `IO ()` approach, this is probably a lot better.