Problems with diacritics

[dscorbett]

U+00A8 DIAERESIS, U+0384 GREEK TONOS, and U+0385 GREEK DIALYTIKA TONOS have non-spacing glyphs. They should be spacing and should not have anchor points.

All the glyphs in the block Combining Diacritical Marks except for U+0308 are spacing. They should be combining.

U+0308 COMBINING DIAERESIS correctly has a combining glyph with an anchor point. However, its contour points have positive x values. Most base glyphs in this font lack anchor points, so if U+0308 is applied to one base, it will appear above the following base. The simplest solution is to shift the glyph left so it has negative x values.