remove TCL_ARRAYS

This patch removes the TCL_ARRAY symbol. This seems to be a leftover
from when pgtcl was around in the backend; if enabled, it causes
array_out to emit bogus array values:

alvherre=# create table bar ( a text);
CREATE TABLE
alvherre=# insert into bar values ('foo"');
INSERT 0 1
alvherre=# select array_append('{}', a) from bar;
array_append
--------------
{"foo""}
(1 ligne)

The correct value is

alvherre=# select array_append('{}', a) from bar;
array_append
--------------
{"foo\""}
(1 ligne)

Of course, the system does not accept the TCL_ARRAY value back.

--
Alvaro Herrera http://www.CommandPrompt.com/
The PostgreSQL Company - Command Prompt, Inc.