Prevent default config entities of disabled modules from being loaded

If a module provides default config for another module, like node module shipping a view (#1806334: Replace the node listing at /node with a view), the config will be loaded regardless of whether or not node is enabled.
Currently, Views works around this by manually storing a key in the config and calling module_exists().

However, this will apply to all config entity types, and this tries to genericize and automate this.

I need to write some tests to provide this is broken.