Put the registration back in a goroutine
Put the registration back in a goroutine

The tests were failing after making this synchronous. The loop may have been
missing events if it was blocked. However, now it passes "msg" as a parameter
to the goroutine to prevent the race condition.

gliderlabs/resolvable,mehulsbhatt/resolvable,gliderlabs/resolvable,mehulsbhatt/resolvable