The sfnt.Buffer embedded in the opentype type caused instances of
it to escape. Move the buffer to Family to avoid that.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Text shaping is a common name for what package measure does. Rename
it to "shape" and move it below the text package.
Signed-off-by: Elias Naur <mail@eliasnaur.com>