The previous hledger-suite image was treated as a monolithic development
image that was never intended to be pulled from directly, at least
outside of the `dfi` build system.
hledger-suite has now been parsed out into separate build targets for
faster maintenance and development, with the final production image
being a massively slimmer "placeholder" image for the built binaries.
`hledger-suite:latest` can now be pulled from directly without pulling
the entire build system and related artifacts.