Constructs function meta-data. Function set implementation classes must
have a public no-args ctor.
Parameters: id - The function set ID. Parameters: displayName - The display name. Parameters: description - Textual description of this function set. Parameters: docUrl - URL for documentation. Parameters: author - Author's name. Parameters: implClass - The fully qualified name of the function setimplementation class. Parameters: nsPrefix - The namespace prefix to use. Parameters: nsURI - The namespace URI to use.
Returns an instance of the class that implements the extension
functions.
Parameters: entityResolver - Implementation class. throws: RepositoryException - if the class could not be found.