[m-rev.] for review: avoid misleading error message

[Zoltan Somogyi]

2022-02-09 12:20 GMT+11:00 "Julien Fischer" <jfischer at opturion.com>:
>> -[Mercury compiler not yet installed -
>> +[$MC_UNAVAIL_MSG compiler not yet installed -
> 
> Delete the words "compiler not yet installed" there.

Done.

>>  ****    cannot use grade '$BEST_GRADE_FOR_COMPILER'
>>  ****    using grade '$GRADE' to compile the compiler
>>  ****    after installation is complete you may reinstall

I also converted this part to use sentences.

> The rest looks fine.

Thanks. The diff is committed.

Zoltan.