Create Anchors for Threats

[mmccool]

Can't link to threats etc. in S&P Guidelines, row columns are missing anchors. Add them (id attributes in table rows).

[mmccool]

Note: ids are currently inferred, so in fact links are possible: e.g. https://w3c.github.io/wot-security/#dfn-malicious-authorized-solution-user works even though that id is not explicitly given. But an explicit id would be better (and more consistent with HTML standard - inferred ids are not mentioned here: https://developer.mozilla.org/en-US/docs/Web/HTML/Element/dfn)

[mmccool]

see also https://html.spec.whatwg.org/multipage/text-level-semantics.html#the-dfn-element

[mmccool]

Link anchors (ids) are actually automatically inserted by ReSpec when the static version is exported. So we don't need to worry about doing this manually, and can close this issue - just use the static version as a target.