Additional fontmake tasks

[twardoch]

Currently, fontmake let's us run ttfautohint

It'd be great if it could also:

• run psautohint
• take the CLI params of pyftsubset and call the fontTools.subset
• do basic font renaming
• optionally do "feature freezing" though I dunt think it's needed

If there were .DesignSpace lib keys to run a series of fontmake builds for different targets, all this could be controlled from .DesignSpace (which I think is the right place) and then a complete build could be done with

fontmake -m my.designspace

[alerque]

Hey Adam, I'm curious what you think of my argument (as for example brought up here in regard to cffsubr) that it would be better if tools like this stuck to doing one job and let other tooling bring it all together — that trying to both do the deep exhaustive work on one topic and also trying to juggle the plate spinning on semi-related topics in one tool is a recipe for a mess?

cf. Comments on #690.

[madig]

If anything, I'd like fontmake to do less. I mean, look at the code, it is byzantine enough already.