Some headings are too long for IETF format

[handrews]

I've never figured out what tool generates this format so I never checked, but see https://tools.ietf.org/html/draft-handrews-json-schema-02#section-8.2.4.2 for one that wraps and looks quite bad.

Also, https://tools.ietf.org/html/draft-handrews-json-schema-02#section-8.2.3 and https://tools.ietf.org/html/draft-handrews-json-schema-02#section-9.2.1 look fine but are too long in the table of contents so it refuses to link them (as far as I can tell that's what's going on).

There might be other sections with this problem, and note that many sections such as 8.2.4.2 are not in the TOC but may still look bad in the formatting.

[handrews]

Most of this will get handled by the PR for #909 so I'll pick up the last bit, too.