We can use the new binding helpers to make this
a little less bothersome. That way, it will need
tweaks less often (only when new fundamental types
are introduced).
Update all the places where we switch over
PangoAttrType to handle PANGO_ATTR_TEXT_TRANSFORM,
and do nothing for now - text-transform support
will land in 4.6.
We were not handling mnemonics vs markup right
in all cases. Rewrite the _-stripping code to
do it during the link parsing, instead of as
a separate function. This avoids the issue of
stripping _ from attribute names in markup.
Add tests.
Fixes: 3706
