Feature Request: Support js functions for onDeploy & afterDeploy actions

[ewingrj]

Overview

TL;DR

It would be great if the onDeploy and afterDeploy actions supported functions instead of only js strings that are eval'd.

[0x-r4bbit]

Thanks @perissology for raising this here. Leaving this here for context: https://gitter.im/embark-framework/Lobby?at=5bdf41385760a73eb43a8c5a