CREATE TABLESPACE SET

I was recently annoyed that I had to do

CREATE TABLESPACE x LOCATION y;
ALTER TABLESPACE x SET (random_page_cost = z);

The attached patch is a quick n' dirty extension to allow the SET
directly on the CREATE statement.

CREATE TABLESPACE x LOCATION y SET (random_page_cost = z);

If people think this is a good idea, I'll clean it up, add
documentation, and submit it to the next commitfest.

--
Vik