Added a SAX property to enable dynamic loading of different character converters.
Added a SAX property to enable dynamic loading of different character converters.

kylieloo/473marc4j,marc4j/marc4j,kylieloo/473marc4j,kylieloo/473marc4j,jasonzou/marc4j,jasonzou/marc4j,marc4j/marc4j,Dyrcona/marc4j,Dyrcona/marc4j