Move Features under separate package

[GAlexIHU]

Overview

The idea with this change is to minimize how much we'll step on each others feet in the following period. The thinking is as follows:

• It was already questionable before whether openmeter/productcatalog was the right place for features
• We most likely will be contributing a significant amount inside openmeter/productcatalog which could&will cause conflicts
• In case productcatalog would ever have subpackages there easily can be circular dependency issues if they depend on feature. (Its not clear if we want that or not)
• It is now very easy to move features once we figure out where it truly belongs (just a bunch of mass replace + aliasing; and then we can remove the aliasing too)
• Currently its used in 4 places in the cloud distribution which is not such a big hassle to fix up

Drawbacks:

• Some variables had to be renamed from feature to feat