Small aesthetic change in ErrorHandling.
The CLI now correctly prints fatal errors.

Because the main loop was wrapped in void, they got swallowed.
Comics.List now reads files correctly.
Comics.List.comics now correctly prints parsing errors.
Fixed parsing bug in comics.

The read function expected Maybe LinearComic instead of LinearComic.
This is fixed now.
Put comics into external scripts.
CLI now only asks for comic name once.

Previously, typing ":list" resulted in the CLI asking for the comic's
name again, which was quite annoying.