Re: pgbench - allow backslash continuations in \set expressions

> FWIW, I looked a bit further and concluded that probably psqlscan.l
> doesn't need to be modified; so likely you could do this across all of
> pgbench's commands without touching psql.  That might be an acceptable
> compromise for now, though I still think that as soon as we have this
> for pgbench, users will start wanting it in psql.

The attached patch adds backslash-return (well newline really) 
continuations to all pgbench backslash-commands.

The attached test uses continuations on all such commands (sleep set 
setshell and shell).

I think that adding continuations to psql should be a distinct patch.

-- 
Fabien.