System validation helpers to be called from your start method

Provide helper functions that establish a common pattern for validating components dependencies and arguments when starting up.

Something like:
```clojure
(defrecord Database
  cmp/Lifecycle
  (start [this]
    (**verify!** ...test-fn... ...maybe-on-error...)
    (when-not (**verify-only?**)
       #_(only when we shouldnt just verify))
    ...start this...))
```