add interceptor category in toml #53
Description
An InterceptorConfigHandler will claim all [interceptor.*] definitions to provide more control than the current "interceptors" property directly on target components (which requires adding that explicitly to any component that should be intercepted).
The [interceptor] component should use the Selector + Condition model to match labels on components. It should hold a reference to either a pre-defined interceptor component (in which case the imports/exports should be validated) or to a generic advice component (in which case the interceptor component will be generated).
depends on #52