Adding a test for unknown TABLE_TYPE

added:
  mysql-test/suite/connect/r/general.result
  mysql-test/suite/connect/t/general.test

mysql-test/suite/connect/r/general.result

+#
+# Testing features not specific to any TABLE_TYPE
+#
+CREATE TABLE t1 (a INT) ENGINE=CONNECT TABLE_TYPE=NON_EXISTING;
+ERROR HY000: Unsupported table type NON_EXISTING

mysql-test/suite/connect/t/general.test

+--echo #
+--echo # Testing features not specific to any TABLE_TYPE
+--echo #
+
+--error ER_UNKNOWN_ERROR
+CREATE TABLE t1 (a INT) ENGINE=CONNECT TABLE_TYPE=NON_EXISTING;
+
+#CREATE TABLE t1 (a INT) ENGINE=CONNECT TABLE_TYPE=FIX FILE_NAME='t1.txt';
+#INSERT INTO t1 VALUES (10);
+#SELECT * FROM t1;
+#--error ER_GET_ERRMSG
+#ALTER TABLE t1 TABLE_TYPE=NON_EXISTING;
+#SELECT * FROM t1;
+#DROP TABLE t1;