[m-rev.] for review: Delete erlang from grade scripts.

[Julien Fischer]

On Mon, 26 Oct 2020, Peter Wang wrote:

> scripts/canonical_grade.sh-subr:
> scripts/final_grade_options.sh-subr:
> scripts/init_grade_options.sh-subr:
> scripts/parse_grade_options.sh-subr:
>    Stop recognising "erlang" as a target or grade component.

That's fine.

Julien.