HAFAS returns notes for journey legs, stopovers and departures.
There are two kinds of notes: "remarks" (in `remL`) and HAFAS
Information Manager (HIM) notes (in `himL`). The former describe
the regular operating situation, e.g. "bicycles allows", whereas
the latter describe cancellations, construction work, etc.
The planned naming scheme for hafas-client:
- hints: notes from `remL` for regular operation
- warnings: notes from `himL` for cancellations, construction, etc
- remarks: both "notes" and "warnings"
This commit prepares the new naming scheme by renaming the
existing parsing logic of `remL` to "hints". Follow-up commits
will add `parseWarning`.
