[m-rev.] for review: \e as ESC, stage 2

[Julien Fischer]

On Sun, 28 Apr 2024, Zoltan Somogyi wrote:

> Add support for \e as the escape char, stage 2.
> 
> doc/reference_manual.texi:
>     Include \e among the list of the escape sequences that are part of Mercury.
> 
> NEWS.md:
>     Announce the change.
> 
> vim/syntax/mercury.vim:
>     Color \e as we do other escape sequences.
> 
> configure.ac:
>     Require the installed compiler to support stage 1.
> 
> library/mercury_term_lexer.m:
> library/rtti_implementation.m:
> library/term_io.m:
>     Use \e where appropriate.

That's fine.

Julien.