The journal/timeclock/timedot parsers, instead of constructing (opaque)
journal update functions which are later applied to build the journal,
now construct the journal directly (by modifying the parser state). This
is easier to understand and debug. It also removes any possibility of
the journal updates being a space leak. (They weren't, in fact memory
usage is now slightly higher, but that will be addressed in other ways.)
Also:
Journal data and journal parse info have been merged into one type (for
now), and field names are more consistent.
The ParsedJournal type alias has been added to distinguish being-parsed
and finalised journals.
Journal is now a monoid.
stats: fixed an issue with ordering of include files
journal: fixed an issue with ordering of included same-date transactions
timeclock: sessions can no longer span file boundaries (unclocked-out
sessions will be auto-closed at the end of the file).
expandPath now throws a proper IO error (and requires the IO monad).
