Fix cancel bug publishing pointers
Fix cancel bug publishing pointers

Since the offline message pointer publish was moved into a separate goroutine
the context was being defer canceled before the publish was finished. This
move the defer inside the goroutine.

gubatron/openbazaar-go,OpenBazaar/openbazaar-go,hoffmabc/openbazaar-go,OpenBazaar/openbazaar-go,hoffmabc/openbazaar-go,OpenBazaar/openbazaar-go,gubatron/openbazaar-go,hoffmabc/openbazaar-go,gubatron/openbazaar-go