This new approach allows filtering out checks from the default set that are
not appropriate for a command, rather than having to list every check
that is appropriate. It also reduces some boilerplate.
Haskell does not define Eq for functions, so I had to go a long way around
with each check having a unique id. Meh.
These were a mistake, they make the type signatures harder to read and
less flexible. The CommandSeek, CommandStart, CommandPerform, and
CommandCleanup types were a good idea, but composing them with the
parameters expected is going too far.
Adds a missing newline when a longnote is followed by a endresult.
Multiple longnotes in a row will now be separated by a blank line, which
could be a bug or a feature depending on taste.
Removed several places where newlines were explicitly displayed after
longnotes.