add strict option

[juunini]

CREATE TABLE "tBl1" ( -- Created table name is "tBl1"
  id int
);

SELECT * FROM tbl1; -- failure
SELECT * FROM tBl1; -- failure
SELECT * FROM TBL1; -- failure
SELECT * FROM "tbl1"; -- failure
SELECT * FROM "tBl1"; -- success

CREATE TABLE tBl2 ( -- Created table name is "tbl2"
  id int
);

SELECT * FROM tbl2; -- success
SELECT * FROM TBL2; -- success
SELECT * FROM tBl2; -- success
SELECT * FROM "TBL2"; -- failure
SELECT * FROM "tbl2"; -- success

Should add strict option.
strict option's default value is true.
will user can optionally set to false.