[autofit] Redesign the recognition algorithm of strong points. In particular, local extrema without horizontal or vertical segments are better recognized: + A + D \ / \ / \ / \ / \ + C \ / B +/ If the distances AB and CD are large, point B wasn't previously detected as an extremum since the `ft_corner_is_flat' function `swallowed' BC regardless of its direction, tagging point B as weak. The next iteration started at B and made `ft_corner_is_flat' swallow point C, tagging it as weak also, et voilĂ . To improve that, another pass gets now performed before calling `ft_corner_is_flat' to improve the `topology' of an outline: A sequence of non-horizontal or non-vertical vectors that point into the same quadrant are handled as a single, large vector. Additionally, distances of near points are now accumulated, which makes the auto-hinter handle them as if they were prepended to the next non-near vector. This generally improves the auto-hinter's rendering results. * src/autofit/afhints.c (af_glyph_hints_reload): Implement it. * src/autofit/afhints.h (AF_FLAGS): Remove no longer used flag `AF_FLAG_NEAR'.