RE: psql - add SHOW_ALL_RESULTS option

Hello Aya-san,

Thanks for this review.

> There is space (+--' '). Please delete it. It is cause of regression test failed.

Indeed, unsure how I could do that. Fixed.

>> IMHO this new setting should be on by default: few people know about \; so
>> it would not change anything for most, and I do not see why those who use
>> it would not be interested by the results of all the queries they asked for.
> I agree with your opinion.

Ok. I did not yet change the default in the attached version, though.

> I test some query combination case. And I found when warning happen, the 
> message is printed in head of results. I think it is not clear in which 
> query the warning occurred.

Indeed.

> How about print warning message before the query that warning occurred?

Sure. It happened to be trickier than I thought to achieve this, because 
there is a callback hook to send notifications.

This attached version does:
  - ensure that warnings appear just before its
  - add the entry in psql's help
  - redefine the function boundary so that timing is cleaner
  - include somehow improved tests

-- 
Fabien.