pgsql: Add CASCADE option to TRUNCATE.

Log Message:
-----------
Add CASCADE option to TRUNCATE. Joachim Wieland

Modified Files:
--------------
pgsql/doc/src/sgml/ref:
truncate.sgml (r1.19 -> r1.20)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/truncate.sgml.diff?r1=1.19&r2=1.20)
pgsql/src/backend/catalog:
heap.c (r1.293 -> r1.294)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/catalog/heap.c.diff?r1=1.293&r2=1.294)
pgsql/src/backend/commands:
tablecmds.c (r1.177 -> r1.178)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/commands/tablecmds.c.diff?r1=1.177&r2=1.178)
pgsql/src/backend/nodes:
copyfuncs.c (r1.327 -> r1.328)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/nodes/copyfuncs.c.diff?r1=1.327&r2=1.328)
equalfuncs.c (r1.263 -> r1.264)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/nodes/equalfuncs.c.diff?r1=1.263&r2=1.264)
pgsql/src/backend/parser:
gram.y (r2.531 -> r2.532)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/parser/gram.y.diff?r1=2.531&r2=2.532)
pgsql/src/backend/tcop:
utility.c (r1.252 -> r1.253)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/tcop/utility.c.diff?r1=1.252&r2=1.253)
pgsql/src/include/catalog:
heap.h (r1.76 -> r1.77)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/include/catalog/heap.h.diff?r1=1.76&r2=1.77)
pgsql/src/include/commands:
tablecmds.h (r1.25 -> r1.26)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/include/commands/tablecmds.h.diff?r1=1.25&r2=1.26)
pgsql/src/include/nodes:
parsenodes.h (r1.301 -> r1.302)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/include/nodes/parsenodes.h.diff?r1=1.301&r2=1.302)
pgsql/src/test/regress/expected:
truncate.out (r1.10 -> r1.11)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/test/regress/expected/truncate.out.diff?r1=1.10&r2=1.11)
pgsql/src/test/regress/sql:
truncate.sql (r1.3 -> r1.4)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/test/regress/sql/truncate.sql.diff?r1=1.3&r2=1.4)