New facilities for the MARC module. The reading - and writing of

New facilities for the MARC module. The reading - and writing of
content are separate methods for the yaz_marc_t handle. The following
read functions are available: yaz_marc_read_iso2709 (Reads MARC in
ISO2709 format), yaz_marc_read_xml (reads MARC in MARCXML/MarcXchange
format). Write functions have prefix yaz_marc_write_.. The existing
utilities yaz_marc_decode_wrbuf and yaz_marc_decode_buf are still
available. Removed support for OAI-MARC and simplexml (not the
simplexml from PHP5).