WIP: elm 0.19.1 work.

Integrates 0.19.0 updates done at:
#450 with updates to 0.19.1 such as
updating to 0.19.1 (with elm directly installed) and some Makefile
updates to make things build.

This still has a couple of runtime issues:
- macros that are defined using a quote or quasiquote at the top-level
  aren't evaluated the final time.
- the perf3 test times out (this may be related to the macros issue).

Add intermediate test for env/fn interaction

It should pass on existing implementations because it is a
prerequisite for an existing test, but small independent tests are
easyer to debug on new implementations.

rexx, ruby: remove extraneous mal files.