Rework how configuration settings are applied. All this time _any_...

Rework how configuration settings are applied. All this time _any_ configuration settings that changes resulted in a complete reload of many catalogs and database entries unnecessairly. It is now more granular and each page applies its own changes as necessary.
This needs extensive testing as I am not sure what other assumption were made when this configuration model was conceived. It now _appears_ to be applying changes only when necessary but I could have missed a few things here and there. Please test.
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