This PR separates the core cpp packs into `codeql/cpp-queries` and
`codeql/cpp-all`.
There are very few lines of code changed. Almost all changes are moving
files around.
Eventually these files will subsume the current `queries.xml` files
at the top of query-containing and library directories. For now they're
just here to support internal testing of the tooling support for them
we're writing on.
Format and contents is a work in progress. If you're not in Semmle,
don't depend on anything here making sense (or staying stable) until
you see the version tags increase to something nonzero.
Andrew Eisenberg
Henning Makholm