MEDIUM: pattern: retrieve the sample type in the sample, not in the keyword description

We need the pattern fetchers and converters to correctly set the output type
so that they can be used by ACL fetchers. By using the sample type instead of
the keyword type, we also open the possibility to create some multi-type
pattern fetch methods later (eg: "src" being v4/v6). Right now the type in
the keyword is used to validate the configuration.
3 files changed