Remove unneeded intermediate executable files.
Remove Cargo.lock from version control system.
Update dependency versions.
Update Dockerfile (converge to update-some-dockerfiles branch).
Apply changes suggested by rustfmt and clippy, or enforced by rustc.
Remove several unneeded clone().
Merge eval and eval-ast, remove quasiquoteexpand and macroexpand.
Report more errors during startup.
- Reorder README to have implementation list after "learning tool"
bullet.
- This also moves tests/ and libs/ into impls. It would be preferrable
to have these directories at the top level. However, this causes
difficulties with the wasm implementations which need pre-open
directories and have trouble with paths starting with "../../". So
in lieu of that, symlink those directories to the top-level.
- Move the run_argv_test.sh script into the tests directory for
general hygiene.
