Modernize the error stream source

The ErrorStreamSource was used to read FED raw data files which were produced on the DAQ1 StorageManager when events could not be processed successfully on the HLT. In DAQ2, an updated version 3 of the FRD format (as defined in IOPool::Streamer::FRDEventMessage) will be used. This pull request enables the ErrorStreamSource to read all versions of the FRD format. It also renames the file to FRDStreamSource to lessen confusion when it will be used as input source for reading BU files (which have nothing to do with errors.) For backward compatibility, the old name ErrorStreamSource is retained as an alias.