pgsql: psql: Add some completion support for CREATE TABLE .. AS

psql: Add some completion support for CREATE TABLE .. AS

"AS" is added as a suggested keyword for CREATE TABLE for a few query
patterns, including the case where a list of columns is given in
parenthesis.

More queries can be now completed with the keywords supported for
queries in a CTAS, after:
CREATE TABLE [TEMP|TEMPORARY|UNLOGGED] <name> [ (...) ] AS

Author: Gilles Darold
Reviewed-by: Jim Jones
Discussion: https://postgr.es/m/e462b251-99a7-4abc-aedc-214688742c80@darold.net

Branch
------
master

Details
-------
https://git.postgresql.org/pg/commitdiff/816f10564a8671918e170a547625584d10587cf4

Modified Files
--------------
src/bin/psql/tab-complete.c | 14 ++++++++++----
1 file changed, 10 insertions(+), 4 deletions(-)