some strange messages

There are a couple of messages in the backend that are probably
misworded:

#: utils/misc/guc.c:1553
msgid "The Unix-domain socket directory to listen to"

I think it should be something like
"Directory where the Unix-domain socket should be created"

#: utils/adt/acl.c:780
msgid "cannot remove the world ACL"

What exactly is "the world ACL"? The code there is not too commented
and I couldn't find out what's this about. Some sort of default or
initial ACL maybe?

#: parser/gram.y:3249
msgid "argument type missing (use NONE for unary operators)"

Maybe the string between parenthesis should be in a separate errhint() ?

--
Alvaro Herrera (<alvherre[a]dcc.uchile.cl>)
"¿Qué importan los años? Lo que realmente importa es comprobar que
a fin de cuentas la mejor edad de la vida es estar vivo" (Mafalda)