get Default Handler
public static MetadataHandler<FloggerMetadataKey.KeyValueHandler> getDefaultHandler(Set<FloggerMetadataKey<? extends Object>> ignored)
Returns a new MetadataHandler which handles all non-ignored metadata keys by dispatching their values to the key itself. This is convenient for generic metadata processing when used in conjunction with something like KeyValueFormatter.
Return
a handler configured with the default key/value handlers and ignored keys.