building from quadratic with tt-hinting

[RosaWagner]

Posted an issue in fontmake googlefonts/fontmake#1045 but it may be an issue with the builder.

Cosimo says that to build a font from quadratic curves + hinting we should do this:

for a font with quadratic sources and manual hinting, in addition to --keep-direction, you could also pass --ttf-curves=keep-quad so cu2qu is skipped as well (it should not modify the quads but it's quicker if you know in advance there are no cubic to convert). Also --keep-overlaps if you're building a static font, so the original quadratic outlines are not messed with.

[simoncozens]

You can set:

reverseOutlineDirection: false
removeOutlineOverlaps: false

The "keep-quad" is just a speed-up. These two argument don't work in the ninja builder, which I'll fix in a moment, but in your case you are not using that because the ninja builder doesn't support vttSources so it falls back to the standard builder.