`CifResource` (and probably resources for other languages) uses `StreamCodeBox(AppStream)`, which flushes per line. This is inefficient in EMF for platform resource paths, which use `PlatformResourceOutputStream`, where this adds lots of overhead per flush. This is not a problem when using e.g. a `FileOutputStream`. Writing files that should take a few milliseconds may then take minutes, so this is a serious performance issue. We should forgo line-based flushing for writing CIF models, etc. It is not necessary for writing them, as they are typically not written to the command line but to files. Implementation suggestions: * Rename `StreamCodeBox` to `AppStreamCodeBox`. * Make `OutputStreamCodeBox` with similar functionality, but optional line-based flushing.