Add several accent/diacritic marks.

*   Narrow `grave`.
*   Recap `grave`, `caron`, `circumflex`.
*   Add accents and diacritic marks, in their spacing versions, corresponding to most of the combining marks used in the precombined characters in the parts of the Windows-1252 set not yet implemented, including those listed below. Addition of the precombined characters will be a separate pass.
    *   `acute`
    *   `cedilla`
    *   `dieresis`
    *   `dotaccent` (not in '1252, included just because it was trivial to derive from `dieresis`)
    *   `macron`
    *   `ring` (not in '1252, but appears in precombined characters in '1252)
    *   `tilde` (not in '1252, but appears in precombined characters in '1252)
        *   This is Unicode "SMALL TILDE", not `~`, which is `asciitilde` in the glyph list