Redirect forced for parent theme

[JiveDig]

Since some of the latest PR's allow Merlin to be used in a child theme or a plugin, we need a better way to declare if/when the redirect should happen. Not sure if the config should allow this or what, but it's confusing to the user now if using Merlin in a child theme or plugin.

Related: https://github.com/richtabor/MerlinWP/issues/133

I had an early tester hit that unexpectedly. https://github.com/maithemewp/mai-demo-importer/issues/3