add FLAC__metadata_simple_iterator_get_block_offset(), FLAC__metadata_simple_iterator_get_block_length(), FLAC__metadata_simple_iterator_is_last()

change default extension for ogg flac from .ogg to .oga (SF#1762492: http://sourceforge.net/tracker/index.php?func=detail&aid=1762492&group_id=13478&atid=113478)

document blocksize strategy bit, RESIDUAL_CODING_METHOD_PARTITIONED_RICE2, new subset sample rates, subset clarification, variable blocksize clarification

Fixed bug where importing non-CDDA cuesheets would cause an invalid lead-out track number; also add requirement for non-CDDA lead-out track number to be 255 (SF#1764105: https://sourceforge.net/tracker/index.php?func=detail&aid=1764105&group_id=13478&atid=113478).

Some MinGW fixes (SF#1684879: https://sourceforge.net/tracker/index.php?func=detail&aid=1684879&group_id=13478&atid=113478)

Fixed bug where using --replay-gain without any padding option caused only a small PADDING block to be created (SF#1760790: https://sourceforge.net/tracker/index.php?func=detail&aid=1760790&group_id=13478&atid=113478)

fix bug where sometimes an existing installation of flac could interfere with the build process (SF#1763690: https://sourceforge.net/tracker/index.php?func=detail&aid=1763690&group_id=13478&atid=113478)

fixed bug compiling flac without ogg support (SF#1760786: http://sourceforge.net/tracker/index.php?func=detail&aid=1760786&group_id=13478&atid=113478)

add new option --no-utf8-convert to flac (SF#973740: http://sourceforge.net/tracker/index.php?func=detail&aid=973740&group_id=13478&atid=363478)