[BUG] require gateway
[BUG] try catch gateway start
Revert "[CHORE] pass callback on process start"

This reverts commit 9be9e829cf721b24a348f65b1541772d78175d23.
Revert "[CHORE] fire callback with error or processes"

This reverts commit 9a5fc4935bb6e755c4a242259bc416fa4acdad37.
Revert "[CHORE] refactor startGateway function to take callback."

This reverts commit 6cf2e71a48801b7b6edee80d28806a48bc83aa17.