website issues #21
Description
- Update hugo books theme to current
- Change "Specs" to "Specifications" in the lhs index on the specs page
- Hide "sysext" entry from the specs index. it's just a legacy alias for UAPI.4. Hence should continue to exist, but not be visible in the index
- the order of the specs should be fixed, i.e. sort by spec number, so that UAPI.12 comes after UAPI.2
- it would be good to have alias urls for the specs that go by number, and forward to the real spec URL. But these alias urls should not show up as separate pages in the index.