[adapters] Use an adapter for serializing entities to a bare python structure which may be used for e.g. JSON export or other and allow to have different serializations for each entity types. Closes #6378035

option_group_changed('port', 'main', 'web')
option_group_changed('query-log-file', 'main', 'web')
option_group_changed('profile', 'main', 'web')
option_group_changed('max-post-length', 'main', 'web')