in printf statements in pngvalid.c, and changed %ud to %lu.

and re-removed mkinstalldirs.

that CCP writes to standard output by default (Martin Banky).

$AUTOHEADER, $AUTOPOINT, $ACLOCAL and $LIBTOOLIZE

Studio 2010 (John Bowler).

and contrib/pngminim/preader/pnglibconf.dfa

depending on PNG_16BIT_SUPPORTED

and fixed a spelling error