filtering hints by type

[derhuerst]

thanks for this tool! i'm trying to use this to validate GeoJSON coming from a web service, so i'm interested only in the fact that the response is valid GeoJSON.

reading the GeoJSON spec, it sounds a lot like the "old-style crs member is not recommended" warning should be labeled as a warning:

OGC CRS URNs such as urn:ogc:def:crs:OGC:1.3:CRS84 shall be preferred over legacy identifiers such as EPSG:4326.

I'd like to propose to add a level field to all hints returned by hint(data). others could continue using this lib just like before, but it would be possible to tell if data is outright invalid or just doesn't comply with recommendations.

[derhuerst]

This would work similar to ESLint, which returns a severity property with each message.