pgsql: Remove sql_inheritance GUC.

Remove sql_inheritance GUC.

This backward-compatibility GUC is long overdue for removal.

Discussion: http://postgr.es/m/CA+TgmoYe+EG7LdYX6pkcNxr4ygkP4+A=jm9o-CPXyOvRiCNwaQ@mail.gmail.com

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/e13486eba05cc46951a34263d19b65d1eca0176b

Modified Files
--------------
doc/src/sgml/config.sgml | 30 ---------------------------
doc/src/sgml/ddl.sgml | 8 +++----
doc/src/sgml/queries.sgml | 8 +++----
src/backend/commands/lockcmds.c | 2 +-
src/backend/commands/tablecmds.c | 8 +++----
src/backend/nodes/makefuncs.c | 2 +-
src/backend/parser/analyze.c | 4 ++--
src/backend/parser/gram.y | 9 ++++----
src/backend/parser/parse_clause.c | 26 +----------------------
src/backend/utils/misc/guc.c | 10 ---------
src/backend/utils/misc/postgresql.conf.sample | 1 -
src/include/nodes/primnodes.h | 3 +--
src/include/parser/parse_clause.h | 1 -
src/include/utils/guc.h | 1 -
14 files changed, 20 insertions(+), 93 deletions(-)