vg/vgpdf: switch to a backend that supports font embedding
we should (probably) consider switching away from bitbucket.org/zombiezen/gopdf/pdf
that isn't maintained much.
and probably switch to github.com/jung-kurt/gofpdf
.
4 reasons:
- it is maintained
- it is stable
- it is on github (so we don't require a mercurial client)
- it supports fonts embedding
the last one is a rather nice feature and allows for better PDF compatibility (w/o relying on fonts metrics being the exact same than the Courier
, Helvetica
and Times
ones.)