Re: ALTER SYSTEM SET command to change postgresql.conf parameters (RE: Proposal for Allow postgresql.conf values to be changed via SQL [review])

If we are going to add ALTER SYSTEM, then I'd like to consider recasting
ALTER ROLE ALL SET in terms of ALTER SYSTEM as well, because the ALTER
ROLE ALL syntax was a hack.  At least it should be possible to consider
various levels of "system".  Who knows, maybe a future version will
allow propagating settings to standby servers?  I don't know what a good
terminology would be, but let's keep some options open.