[parser] mysql: update sql-mode default (#45)
[parser] mysql: update sql-mode default (#45)

Change TiDB to use same default as MySQL 5.7
kyle-wang/tidb,kyle-wang/tidb,ngaut/tidb,kyle-wang/tidb,coocood/tidb,ngaut/tidb,c4pt0r/tidb,c4pt0r/tidb,pingcap/tidb,pingcap/tidb,c4pt0r/tidb,c4pt0r/tidb,ngaut/tidb,pingcap/tidb,kyle-wang/tidb,ngaut/tidb,pingcap/tidb,c4pt0r/tidb,kyle-wang/tidb,coocood/tidb,pingcap/tidb,c4pt0r/tidb,pingcap/tidb,ngaut/tidb,kyle-wang/tidb,ngaut/tidb