Refactor fixupResponse in preparation of moving it to snap-core.
Refactor fixupResponse in preparation of moving it to snap-core.

23Skidoo/snap-server,sopvop/snap-server,23Skidoo/snap-server,k-bx/snap-server,23Skidoo/snap-server,k-bx/snap-server,snapframework/snap-server,sopvop/snap-server,snapframework/snap-server,snapframework/snap-server