Tagged release v1.19.0

6954422 Remove procedure title from dgf dutch complete protocol.
ca86167 fix(dgf): Change participant description format. Create custom serializer class for dgf procedures
c106a7c Fix dgf protocols.
34821bc Remove mininal value from dgf dutch complete protocol.
c04876a Fix dgf protocols.
47e5465 Handle error according to the content-type header
76f64e9 Fix link to fg.