The build agents will now automatically install and activate the
Emscripten version found in minimum-versions.inc.sh when configuring
WASM projects. For developer machines, this behaviour can be enabled by
setting the environment variable `KEYMAN_USE_EMSDK` (recommended).
This will be back-ported to 17.0 so that we can ensure that all builds
use a consistent Emscripten version.
This adds references to various data sources such as Unicode. At
present, this is informational only, not used by any scripts, but the
intent is that in the future we reference this for any scripted data
updates.