SIGSEV when sending to channel without info

[nolanlum]

panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x0 pc=0x6d99d1]

goroutine 26 [running]:
github.com/nolanlum/tanya/gateway.(*SlackClient).SendMessage(0xc0000ce2d0, 0x0, 0xc0006e43e0, 0x37, 0xc00006ff38,
0xc00056b3e0)
        /Users/nolanlum/golang/src/github.com/nolanlum/tanya/gateway/slack.go:365 +0x61
main.(*corpusCallosum).SendPrivmsg(0xc00000e060, 0xc0007c6b60)
        /Users/nolanlum/golang/src/github.com/nolanlum/tanya/main.go:165 +0xfe
github.com/nolanlum/tanya/irc.handleIncomingMessage(0x81dc20, 0xc0007c6b60, 0x826520, 0xc00000e060)
        /Users/nolanlum/golang/src/github.com/nolanlum/tanya/irc/server.go:150 +0x66
github.com/nolanlum/tanya/irc.(*Server).handleIncomingMessageRouting(0xc000060d20, 0xc00001ad20)
        /Users/nolanlum/golang/src/github.com/nolanlum/tanya/irc/server.go:134 +0x1da
created by github.com/nolanlum/tanya/irc.(*Server).Listen
        /Users/nolanlum/golang/src/github.com/nolanlum/tanya/irc/server.go:69 +0x24f