This commit does kind of a lot to get cass(1) over the finish line.
For one it implements all the CLI functions (well, almost all) with
their respective parameters, and also creates a new `gen` module which
uses the IR stream to generate a new file based on the old one, while
updating header fields that need to be updated (currently only
`version`).
This version does nothing with the actual header values, and probably
has a lot of bugs. More documentation will follow in future
cassiopeia commits.
This allows a few things: a, it's a persistant format that we can
mirror to disk again, AND can adapt because all type information is
known, and it allows for new entries to be added to the IR more
easily, without having to worry about exact formatting, or
re-inferring order from the TimeFile abstraction.
Katharina Fey