we change mymysql to go-sql-driver and use insert unhex()
  for any dangerous data type.

	修改：     doc/example/main_test.sh

merge by xiaomi

  1. remove Index_Comment in ShowIndex function
  2. remove mysql client deps in Makefile

  1. update vendor pingcap/parser
  2. Makefile add docker contain stop wait
  3. -report-type=rewrite when syntax error, print error info not empty

not fix too many connections yet

  change `connect` to `docker-connect`
  add `docker-it` for attaching into container

  RES.009 not consider about "and", "or"... Operator in
  BinaryOperationExpr

 DSN 解析优化, 并支持密码特殊字符

merge by xiaomi