This is no longer a TODO.
Remove synchronous ProcessRequest.
Remove precondition from routes as it's not been implemented.
Add feature switch infrastructure
Remove Enabled property from feature and associated tests.

We are going to use IFeatureSwitch instances for this instead.
Replace ApplicationContext with FeatureSwitchboard.

Good riddance, its name was confusing and unclear.

The IOC container is also now configured at application and feature set level.