Use Go1.11 module (#5743)

* Migrate to go modules

* make vendor

* Update mvdan.cc/xurls

* make vendor

* Update code.gitea.io/git

* make fmt-check

* Update github.com/go-sql-driver/mysql

* make vendor

vendor/github.com/lib/pq/error.go

@@ -153,6 +153,7 @@ var errorCodeNames = map[ErrorCode]string{
 	"22004": "null_value_not_allowed",
 	"22002": "null_value_no_indicator_parameter",
 	"22003": "numeric_value_out_of_range",
+	"2200H": "sequence_generator_limit_exceeded",
 	"22026": "string_data_length_mismatch",
 	"22001": "string_data_right_truncation",
 	"22011": "substring_error",
@@ -459,6 +460,11 @@ func errorf(s string, args ...interface{}) {
 	panic(fmt.Errorf("pq: %s", fmt.Sprintf(s, args...)))
 }
 
+// TODO(ainar-g) Rename to errorf after removing panics.
+func fmterrorf(s string, args ...interface{}) error {
+	return fmt.Errorf("pq: %s", fmt.Sprintf(s, args...))
+}
+
 func errRecoverNoErrBadConn(err *error) {
 	e := recover()
 	if e == nil {
@@ -487,7 +493,8 @@ func (c *conn) errRecover(err *error) {
 			*err = v
 		}
 	case *net.OpError:
-		*err = driver.ErrBadConn
+		c.bad = true
+		*err = v
 	case error:
 		if v == io.EOF || v.(error).Error() == "remote error: handshake failure" {
 			*err = driver.ErrBadConn