upgrade irc-go to latest master

go.mod

 	github.com/go-ldap/ldap/v3 v3.1.7
 	github.com/go-sql-driver/mysql v1.5.0
 	github.com/goshuirc/e-nfa v0.0.0-20160917075329-7071788e3940 // indirect
-	github.com/goshuirc/irc-go v0.0.0-20190713001546-05ecc95249a0
+	github.com/goshuirc/irc-go v0.0.0-20200311142257-57fd157327ac
 	github.com/mattn/go-colorable v0.1.4
 	github.com/mattn/go-isatty v0.0.10 // indirect
 	github.com/mgutz/ansi v0.0.0-20170206155736-9520e82c474b

go.sum

 code.cloudfoundry.org/bytefmt v0.0.0-20190819182555-854d396b647c/go.mod h1:wN/zk7mhREp/oviagqUXY3EwuHhWyOvAdsn5Y4CzOrc=
 code.cloudfoundry.org/bytefmt v0.0.0-20200131002437-cf55d5288a48 h1:/EMHruHCFXR9xClkGV/t0rmHrdhX4+trQUcBqjwc9xE=
 code.cloudfoundry.org/bytefmt v0.0.0-20200131002437-cf55d5288a48/go.mod h1:wN/zk7mhREp/oviagqUXY3EwuHhWyOvAdsn5Y4CzOrc=
+github.com/DanielOaks/go-idn v0.0.0-20160120021903-76db0e10dc65/go.mod h1:GYIaL2hleNQvfMUBTes1Zd/lDTyI/p2hv3kYB4jssyU=
 github.com/davecgh/go-spew v1.1.0 h1:ZDRjVQ15GmhC3fiQ8ni8+OwkZQO4DARzQgrnXU1Liz8=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/docopt/docopt-go v0.0.0-20180111231733-ee0de3bc6815 h1:bWDMxwH3px2JBh6AyO7hdCn/PkvCZXii8TGj7sbtEbQ=
 github.com/goshuirc/e-nfa v0.0.0-20160917075329-7071788e3940/go.mod h1:VOmrX6cmj7zwUeexC9HzznUdTIObHqIXUrWNYS+Ik7w=
 github.com/goshuirc/irc-go v0.0.0-20190713001546-05ecc95249a0 h1:unxsR0de0MIS708eZI7lKa6HiP8FS0PhGCWwwEt9+vQ=
 github.com/goshuirc/irc-go v0.0.0-20190713001546-05ecc95249a0/go.mod h1:rhIkxdehxNqK9iwJXWzQnxlGuuUR4cHu7PN64VryKXk=
+github.com/goshuirc/irc-go v0.0.0-20200311142257-57fd157327ac h1:0JSojWrghcpK9/wx1RpV9Bv2d+3TbBWtHWubKjU2tao=
+github.com/goshuirc/irc-go v0.0.0-20200311142257-57fd157327ac/go.mod h1:BRnLblzpqH2T5ANCODHBZLytz0NZN2KaMJ+di8oh3EM=
 github.com/hpcloud/tail v1.0.0 h1:nfCOvKYfkgYP8hkirhJocXT2+zOD8yUNjXaWfTlyFKI=
 github.com/hpcloud/tail v1.0.0/go.mod h1:ab1qPbhIpdTxEkNHXyeSf5vhxWSCs/tWer42PpOxQnU=
 github.com/mattn/go-colorable v0.1.4 h1:snbPLB8fVfU9iwbbo30TPtbLRzwWu6aJS6Xh4eaaviA=

vendor/github.com/goshuirc/irc-go/ircmsg/message.go

 	Prefix         string
 	Command        string
 	Params         []string
+	forceTrailing  bool
 	tags           map[string]string
 	clientOnlyTags map[string]string
 }
 
+// ForceTrailing ensures that when the message is serialized, the final parameter
+// will be encoded as a "trailing parameter" (preceded by a colon). This is
+// almost never necessary and should not be used except when having to interact
+// with broken implementations that don't correctly interpret IRC messages.
+func (msg *IrcMessage) ForceTrailing() {
+	msg.forceTrailing = true
+}
+
 // GetTag returns whether a tag is present, and if so, what its value is.
 func (msg *IrcMessage) GetTag(tagName string) (present bool, value string) {
 	if len(tagName) == 0 {
 	return ircmsg.line(tagLimit, clientOnlyTagDataLimit, serverAddedTagDataLimit, truncateLen)
 }
 
+func paramRequiresTrailing(param string) bool {
+	return len(param) == 0 || strings.IndexByte(param, ' ') != -1 || param[0] == ':'
+}
+
 // line returns a sendable line created from an IrcMessage.
 func (ircmsg *IrcMessage) line(tagLimit, clientOnlyTagDataLimit, serverAddedTagDataLimit, truncateLen int) ([]byte, error) {
 	if len(ircmsg.Command) < 1 {
 
 	for i, param := range ircmsg.Params {
 		buf.WriteByte(' ')
-		if len(param) < 1 || strings.IndexByte(param, ' ') != -1 || param[0] == ':' {
-			if i != len(ircmsg.Params)-1 {
-				return nil, ErrorBadParam
-			}
+		requiresTrailing := paramRequiresTrailing(param)
+		lastParam := i == len(ircmsg.Params)-1
+		if (requiresTrailing || ircmsg.forceTrailing) && lastParam {
 			buf.WriteByte(':')
+		} else if requiresTrailing && !lastParam {
+			return nil, ErrorBadParam
 		}
 		buf.WriteString(param)
 	}

vendor/modules.txt

 # github.com/goshuirc/e-nfa v0.0.0-20160917075329-7071788e3940
 ## explicit
 github.com/goshuirc/e-nfa
-# github.com/goshuirc/irc-go v0.0.0-20190713001546-05ecc95249a0
+# github.com/goshuirc/irc-go v0.0.0-20200311142257-57fd157327ac
 ## explicit
 github.com/goshuirc/irc-go/ircfmt
 github.com/goshuirc/irc-go/ircmatch