[website] Update last version of 2.0 doc

Update testharness.js from upstream.

[simd] Add additional test input for i32x4.dot_i16x8_s (#1955)

[interpreter] opam release 2.0.2

[spec/interpreter] Make sources build and run with current Sphinx & P…

…ython

Update TEST.md

Allow multiple pdf/html builds

[interpreter] Makefile tweaks

[interpreter] Release 2.0 package

[spec] "version 2.0" -> "release 2.0" (#1452)